Another Fine Addition to Their Collection: Mariners Acquire Brendan Donovan in Three-Team Swap

The first thing Chaim Bloom did after taking over baseball operations in St. Louis was trade away everything that wasn’t nailed down. Sonny Gray? Thanks for your contributions, now go try to win a ring in Boston. Willson Contreras? Gone, and to the same team. Nolan Arenado? Thanks for the memories, enjoy the desert. With those trades sorted, he’s moved on to step two: prying up some of those aforementioned nails to make more deals. The most recent shoe to drop in the Cardinals retooling might be the biggest one, though. Brendan Donovan is now a Seattle Mariner, the key piece in a three-team trade that sends Ben Williamson to Tampa Bay and a heaping helping of prospects and draft picks to the Cardinals.

Donovan isn’t a household name like many of the best Cardinals of recent years, but that has far more to do with the team’s middling success of late than any lack of talent. His combination of versatility and offensive firepower calls to mind Ben Zobrist, and unlike almost every other flexible defender who gets compared to Zobrist, this one actually makes sense. Zobrist ran a 121 wRC+ during his seven-year peak. Donovan’s career mark is 119, the same as his 2025 total. He’s under team control for two more years at a reasonable rate, too: $5.8 million this year, with his last trip through arbitration set for 2027.

“A plus bat who can play defense everywhere” generally isn’t a good title to have applied to you. That’s because most of the hitters who receive that label either aren’t plus bats, don’t play good defense, or both. But as I mentioned, that’s not Donovan, and we might as well examine each of those two skills, as he’s the entire reason this trade happened, the best player going to any of the three clubs by a mile.

On offense, Donovan plays like a rough approximation of Steven Kwan. His standout skill is the kind of batting eye/contact combo you’d draw up in a lab. If you throw him something outside of the strike zone, he’s probably not going to swing at it. He chased just 25% of the bad pitches he saw in 2025, a 70th-percentile mark league wide and coincidentally the worst mark of his career. When he did swing, he made contact at a 95th-percentile clip, with a swinging strike rate less than half the big league average. That means that he takes a fair number of walks even though pitchers have no interest in giving him a free pass.

Like I said, that’s basically Steven Kwan. The difference is that Donovan swings the bat six ticks faster on average. He posts league average exit velocities thanks to a respectably fast bat and an absolute mountain of bat control, with his squared-up rate in the 96th percentile. Let’s put it this way: Donovan has a career 42.4% hard-hit rate. Kwan has a career rate of 20%, while Luis Arraez checks in at 26%. That combination means that Donovan’s line drives skip past outfielders and to the wall a lot more frequently than his less-powerful brethren. His career .130 ISO isn’t exactly gaudy – the league average hovers around .160 – but it’s spectacular in the context of the rest of his offensive skills.

Even better for the Mariners, Donovan looks to me like a solid fit for their park. T-Mobile is brutal for hitters, but it’s less punishing for lefties, particularly lefties who get a lot of value from singles and doubles. It’s not even so cavernous that he can’t hit homers there; Busch Stadium is tougher for lefty home run hitters. The biggest thing that makes T-Mobile a pitcher’s park is how much more frequently hitters strike out there. I truly can’t tell you exactly why that is — theories abound — but knowing that’s the problem, I don’t hate a guy who just doesn’t strike out as a solution.

Hitting somewhere near the top of the order, Donovan is going to put opponents in a bind. He gets on base a ton. He hits for a high enough average, and does enough damage, that just lobbing the ball down the middle isn’t a great counter. With at least one of Cal Raleigh or Julio Rodríguez presumably lurking behind him, letting him reach base is going to feel very bad. We’re projecting him as the fourth-best Mariners hitter, behind those two and Josh Naylor, but I’ll go ahead and call it now: Donovan is going to be the hitter that pitchers are most annoyed to face. Snap off three perfect sliders against Raleigh or Rodríguez, and you can probably get them out. Snap off three perfect sliders against Donovan, and it’s probably a 2-1 count.

While Donovan’s offensive upside is obvious, his defensive value is more nebulous. Yes, he won a Gold Glove in 2022, but it was the utility Gold Glove that seems to sometimes just reward guys who play multiple positions, rather than guys who play multiple positions well. He’s played more second base than any other position in the majors, and he’s roughly average there: -5 DRS, +1 FRV. He’s been good in a small sample at third, bad in a small sample at first, and “wait, what why are you even trying this?” in an even smaller sample at short.

His second-most-frequent position isn’t any of those infield spots, but left field. I think he’s an adequate outfield defender, though our models are mixed: DRS thinks he’s been two runs above average in his 1,450 innings, while Statcast’s FRV thinks he’s been five runs below average. As far as I’m concerned, I wouldn’t want to play him out there but wouldn’t feel awful if I had to. In fact, that just about describes Donovan everywhere on the diamond: remarkably competent.

In Seattle, that’s going to mean a heaping helping of third base to start out. We had Williamson atop the depth chart there before this trade, and not much behind him. Donovan is an easy substitution at the hot corner, but he can do more than that. Cole Young is coming into the year with the inside track on the second base job, but he also looked overmatched at the plate in his 77-game major league debut last year. J.P. Crawford’s fielding is headed south, and he’s more of an offensive contributor than a key fielder these days. That offense cratered in the second half last year, though, so the future looks uncertain. Top shortstop prospect Colt Emerson is knocking on the door, but we aren’t sure if he’ll stick at short long-term, and he’d be a better fit at third than at second.

In other words, the infield is a complicated combination of moving pieces, an intricate puzzle to be solved. What better way to handle that than with a guy who plays all over the place? No matter who the odd man out is, there’s probably some configuration involving Donovan that works. That’s great news for a Mariners team that had to play some dicey bats to make their infield defense work in 2025. They handed 684 plate appearances to the combination of Williamson, Dylan Moore, and Donovan Solano last year, and got an 80 wRC+ and meh defense in the aggregate for their trouble. That’s a Donovan-sized hole that would add something like three wins if filled with the genuine article.

To make that enormous upgrade, the Mariners sent the Cards two intriguing young prospects, Jurrangelo Cijntje and Tai Peete, as well as a Comp Round B pick. The headliner of the deal is Cijntje, a 2024 first round pick who is most notable for his switch-pitching. He has monster potential as a righty, sitting in the upper 90s with a nasty fastball and secondaries that flash very well at times. As a lefty, he’s more of a matchup guy; lower 90s, inconsistent shape on his secondaries, intermittent command problems. He’s a 22-year-old who is doing something that almost no one has ever done, so it’s hardly surprising that he’s still developing, but right now he looks like a righty starter plus a little novelty value. The Mariners were reportedly planning on using him as a righty to start spring training, and it wouldn’t shock me to see the same in St. Louis.

That’s an excellent addition to their stable of young pitching prospects, and I’d put him second on that list behind only Liam Doyle, the fifth pick in last year’s draft. Cijntje is a phenomenal athlete who has the capability to improve pretty much across the board, but he’s still a work in progress. As Brendan Gawlowski put it in Cijntje’s write-up for our recent Mariners prospect list, “Catch him on the right day and you might put a no. 2 grade on him. But he’s inconsistent, perhaps not unexpectedly given how many reps he’s lost. His velo can dip mid-outing, and… he’ll lose his release point and start spraying the ball everywhere but the target.” Despite his intermittent command, he racked up gaudy strikeout numbers in his first pro season by outstuffing people, to borrow Brendan’s phrase. If he doesn’t have the command to be a starter, he has the stuff to close as a righty, and then there’s still the whole switch-pitching thing. In other words, there’s a lot of variance in the future outcomes here.

Do I know how the Cardinals will use him? I don’t even have a clue. Seattle struggled with this exact question last year. While he’s clearly better as a righty, that still leaves a lot of options. Is he a righty starter plus a lefty reliever, but only one at a time? An ambidextrous closer? A righty starter who is his own LOOGY? A true switch-pitcher who wears a six-fingered glove to the mound and goes all Pat Venditte on guys? The most likely outcome is the boring one — a righty starter with minimal lefty pitching — but there’s a chance that he ends up being very fun. He’s a 50 FV prospect on The Board, and I like the odds of him developing a little bit better than that.

Peete was a first-rounder a year before Cijntje as a high schooler out of Georgia. He’s also a phenomenal athlete, with plus raw power, a strong arm, and easy plus speed. He took up center field as a professional and looked very good in the outfield in 2025. There’s just one problem: his bat control. Now, the hit tool is just one of the five tools, but it’s surely the most important one. Peete has struck out around 30% of the time, and he’s done that very consistently across multiple levels. As Brendan noted, it’s the scary kind of strikeout problem, too: a 44% whiff rate against breaking pitches, big non-competitive hacks at fastballs out of the zone, everything you can imagine. Back when I used to hunt for breakout prospect picks, I cared a lot about strikeouts at the lower levels. If you’re swinging and missing that often against 20-year-olds, the majors might be out of the question.

The counter to that is that data can lie. Sure, batters who strike out 30% of the time in A-ball usually don’t pan out. But those batters tend to be bad. I mean, obviously – they’re striking out a lot in the low minors. Teams draft lots of players who even they don’t think will reach the majors. They give a lot of playing time to long shots and development projects. Peete’s cohort of whiff-prone minor leaguers almost certainly looks nothing like him. He’s a tooled-out first rounder who might be able to contribute in the majors even if he never hits. It’s reasonable to give him a little grace here. Sure, most players like him don’t develop their offense enough to hit major league pitching, but if he does, the upside is enormous. We have him as a 40+ FV, but with huge error bars; there are detailed write-ups of both him and Cijntje on that aforementioned Mariners list.

Oh yeah! The Rays got in on this trade too, as they are wont to do. They sent Colton Ledbetter and a Comp Round B pick of their own to the Cardinals and got Williamson from Seattle in exchange. Let’s cover the St. Louis side first, just to get that out of the way. Ledbetter is a 24-year-old outfielder who will likely start 2026 in Double-A. Here’s Eric Longenhagen on the last player St. Louis is receiving:

After two underclass seasons at Samford, Ledbetter made a successful transition to the SEC with Mississippi State in 2023 and was Tampa’s second round pick. He hit for power at High-A Bowling Green (45 extra-base hits in 109 games, .484 SLG), but struck out at an alarming 28.3% clip. He cut his strikeout rate to 23.9% at Double-A Montgomery in 2025, but lost the sexy power (just seven homers, .378 SLG), partially due to the hitting environment of the Southern League. Ledbetter is going to swing underneath a lot of fastballs and be a below-average contact hitter in the big leagues, but he has extra-base power to all fields against pitches in the bottom two thirds of the zone. It’s not huge raw power, more average, but Ledbetter has feel for getting underneath the baseball and is going to spray a lot of doubles.

Though he’s played some center field, he’s not speedy enough to be a team’s primary center fielder and should play in the corners (mostly right field). There are a lot of flawed part-time outfielders with similar strikeout issues, but who have more power than Ledbetter (a relatively maxed out 24-year-old) has or is apt to have. So I consider him a lesser, 1-ish WAR version of a platoon outfielder, a 40-FV prospect. He’ll be competing for a 40-man spot throughout 2026.

A Comp Round B comes between the second and third rounds of the draft, with the Cardinals slated to receive picks 68 and 72. The slot value around there is about $1.25 million, and that makes it a valuable trade commodity, whether the Cards are looking to increase the size of their draft pool by taking someone underslot there and splashing the money elsewhere, or just plan to draft the best player available. The underslot plan gets a lot better with two of these picks – an extra $2 million and change is a meaningful amount of overslot money to offer. Comp Round B picks from recent years have turned into 40/40+ FV players on average, so that’s a decent rule of thumb if you’re trying to convert picks into prospect terms you’re more used to, but I think the value is higher than that. They’re a nice addition to the trade, and I’d value either pretty close to where I value Peete, but clearly below Cijntje.

Williamson’s inclusion in the deal makes a lot of sense for the Rays as they try to patch together a strange combination of infielders. He looks to me like an elite defensive third baseman, and our prospect team and DRS concur. He’s mainly played third as a professional, but I think that’s because the Mariners had a few options blocking him at second, and the Rays have historically been very open to moving defenders around the infield.

That’s good for a few reasons. First, the obvious place they can use Williamson is as a platoon partner for fellow recent three-team-trade acquisition Gavin Lux. Lux is a mediocre defensive second baseman with enormous platoon splits. Williamson isn’t a good hitter, but Lux has a career 54 wRC+ against lefties. Williamson’s bat would be an upgrade on that, and his glove would be a huge help too.

Second, there’s at least some chance that the Rays are getting out of the Taylor Walls business. Walls makes me question my sanity every year, and I bet the Rays feel similar confusion at times. He’s a plus defender, but in a way that Statcast’s defensive metrics just don’t buy. On the other hand, his +17 defense at short in only 720 innings (DRS’ estimate) isn’t credible either. Baseball Prospectus’ RDA has him somewhere in the middle, and that seems reasonable to me, but make no mistake, this is a tricky defensive evaluation.

On the other hand, the offensive evaluation is easy: He stinks. Walls has a career 70 wRC+, a career-high mark of 84, and a career .195/.286/.298 slash line if you’re not a big wRC+ fan. In other words, he’s an offensive black hole. At age 29, there’s not a lot of hope that he’s going to improve. His walk rate plummeted in 2025 when pitchers realized he has a career .104 ISO and started flooding the zone; you can imagine things tilting even further from here. In other words, a backup plan seems wise. Now, the long-term backup plan isn’t even really a backup, it’s top prospect Carson Williams. He had a rough 2025, though, and his 40% strikeout rate in a 100-plate appearance cup of coffee means that the Rays probably shouldn’t count on him breaking out early in 2026. Williamson might not have much professional experience at shortstop, but I’m pretty sure Tampa Bay will at least try him there.

I’m probably singing Williamson’s praises a little too much here. Like Walls, there’s a decent chance that he can’t hit major league pitching for long. If you think Walls didn’t hit for much power last year, wait until I tell you about Williamson’s .058 ISO and one homer in 295 plate appearances. But he’s a nice rotational infielder, and Tampa Bay loves its nice rotational infielders. I don’t think this is the same kind of coup for the Rays that the Lux deal was, but I appreciate what they’re doing here by shaping their roster in the direction they want by stepping in as a middleman in the trade to make one team’s return (St. Louis’, in this case) match up more closely with its heart’s desire.

Speaking of what the Cardinals most desire, it’s time for some trade grades. The Rays get a B- from me, which works out. I think of their organization as a machine for turning slightly positive EV decisions into big edges, basically aiming for as many B- deals as possible. Small edges are only small if they don’t compound. This fits pretty much perfectly into their strategy – but since it affects their franchise meaningfully less than the two other teams in the trade, they get only a short paragraph.

The Cardinals look like they’re not going to stop until the major league roster is devoid of contributors who are approaching free agency. Donovan was the prize of their hoard of trade chips, and they opted for a return that’s quantity over quality but has a clear headliner. Cijntje is risky but he has a huge ceiling, the exact kind of pitcher the Cardinals seem to be aiming for as they rebuild their farm system. Peete and Ledbetter are more in the dart throw vein, but as I love mentioning in these trade evaluations, the best way to be good at dart throws is by throwing a lot of darts. Two Comp Round B picks mean that the Cards are going to have a ton of draft flexibility; while they draft 13th this year, they could feasibly try to float someone from the top five with all the extra bonus money they can offer thanks to their expanded pool. Add it all up, and I think that the Cardinals got fair value for Donovan – my surplus value model has them coming out ahead, but that’s pretty much always the case when you trade the best player in a deal that features five players and two draft picks.

The Mariners, meanwhile, have pulled off a nifty little renovation. Between Naylor and Donovan, they’ve made their offense a lot OBP-heavier than it had been, and stacking OBP is very valuable when you already have a good offense. Cijntje was a strange fit on a team with elite starters already; Donovan is going to be phenomenally more useful to them. Williamson is a valuable major leaguer, but he was getting squeezed by the prospects coming up behind him and Donovan’s arrival, so he was expendable. Peete is the sort of guy who gets moved to rebuilders from contenders: tooled up, inconsistent, and probably in need a lot of playing time to figure out what’s there. It’s a classic case where a dime and four nickels are less useful to the Mariners than a quarter. You can’t lean in this direction too frequently, but I think that this was an excellent time for Seattle to use minor leaguers who weren’t in the team’s immediate plans to chase short-term improvement.

So that’s the deal. The Rays get some needed insurance on the infield. The Cardinals begin the part of their rebuild where they take the roster down to the studs, all while hoping Cijntje’s upside will raise the ceiling. And the Mariners? They reinforce the top of their lineup with Donovan, who our own Davy Andrews has compared to a breakfast nook. Not that I’m sure the nickname will stick.