Mariners Land Another Big Bat, Returning Eugenio Suárez to the Emerald City

For the second time in eight days, the Mariners have upgraded their lineup by landing a corner infielder from the Diamondbacks in exchange for multiple prospects. On July 24, they acquired first baseman Josh Naylor in exchange for a pair of young pitchers, and on Wednesday night they brought back All-Star third baseman Eugenio Suárez for a three-prospect package.

The full trade sends the 34-year-old slugger, a pending free agent, to Seattle in exchange for 24-year-old first baseman Tyler Locklear, 24-year-old righty Hunter Cranton, and 25-year-old righty Juan Burgos; both Locklear and Burgos have a bit of major league experience. This is Suárez’s second go-round in Seattle. President of baseball operations Jerry Dipoto previously acquired him and Jesse Winker from the Reds as part of a six-player deal in March 2022, one driven in part by Cincinnati’s desire to dump the last three years and $35 million on Suárez’s contract. He served the Mariners well, totaling 53 homers and 7.8 WAR with a 118 wRC+ in two seasons, and helping them end their epic playoff drought in 2022. Dipoto traded him to the Diamondbacks in November 2023 for Carlos Vargas and Seby Zavala, and he’s been even more productive in Arizona, clubbing 66 homers and 7.0 WAR with a 127 wRC+.

Those Arizona numbers conceal a major turnaround:

Suárez started the 2024 season very slowly. As I noted last year, among qualifiers he had the majors’ second-lowest wRC+, third-lowest slugging percentage, and fourth-lowest batting average through the end of June, but he turned things around midseason thanks in part to his use of a new robotic hitting machine called a Trajekt Arc, which projects video of a pitcher’s delivery at game speed and marries it up with an accurate approximation of his offerings, including the release point and tempo. Suárez, whose attitude and work ethic drew praise from manager Torey Lovullo even when he was struggling, incorporated the contraption into his pregame routine at Chase Field, cycling through each pitcher’s repertoire before home games.

Additionally, as MLB.com’s Mike Petriello detailed in a lengthy Bluesky thread last Friday, Suárez has made some mechanical changes that have helped fuel his breakout — changes captured by Statcast’s batting stance metrics. Since the start of 2024, Suarez has moved forward in the batter’s box by about nine inches, and has opened his stance dramatically, from nine degrees to 16 degrees over the course of last season, and then from 19 degrees to 27 degrees this year:

You can see an animated GIF of the way Suárez’s feet have moved here. Below is a before-and-after video showing Suárez’s first and final home runs Chase Field with the Diamondbacks.

Less obvious from that clip is the way Suarez’s intercept point has gotten closer to the pitcher, increasing from 2.8 inches in front of the plate in March/April 2024 to 15.1 inches in front by the end of the season, a gradual shift of a couple of inches per month. The trend has continued into 2025, increasing from 16.7 inches in front in March/April to 19 inches in July.

The results have been impressive, his improvement dramatic. From July 1 through the end of last season, Suárez ranked third in the majors in homers, fifth in WAR and 10th in wRC+ — a performance that made picking up his $15 million option a no-brainer. He’s carried that over into what’s been more or less a career year, highlighted by a four-homer game against the Braves on April 26. He currently leads the NL in RBI (87) while ranking third in both home runs and slugging percentage, ninth in wRC+, and tied for 15th in WAR. For the 13-month span since last July 1, only Shohei Ohtani, Aaron Judge, and new (old) teammate Cal Raleigh have outhomered him, with Judge and Ohtani the only ones with higher slugging percentages; Suárez is tied for eighth in wRC+ and ninth in WAR in that span.

All of which is to say that this is no fluke. Suárez’s 2025 performance is backed by a career-high 51.1% hard-hit rate, and both his 91.1 mph average exit velocity and 14.9% barrel rate are within an eyelash of his career highs. He’s outdoing his .512 xSLG thanks in part to a career-high 30.1% pulled air rate, the ninth-highest in the majors.

Suárez does strike out with some frequency, though his 26.8% rate is actually his lowest since 2018; he was at 31% for his previous stretch in Seattle. He’s adopted a more aggressive approach since that stint:

For as much as those rates have changed, Suárez still sees far more pitches per plate appearances than Naylor, who was seeing an NL-low 3.22 P/PA at the time of the trade and ranked sixth in first-pitch swing rate at 43.5%. Suárez’s more aggressive approach has given him a chance to annihilate more fastballs. He’s slugging .633 with 12 homers in 128 PA against four-seamers while averaging 94.9 mph in exit velocity; by comparison, he slugged .485 with 10 homers in 225 PA and a 91.4 mph EV against heaters last year, and .461 with 11 homers in 225 PA with a 93.5 mph EV in 2023. He’s slugging .625 with an 88.9 mph EV against sliders, up from .426 with an 85.6 mph EV last year.

If there’s a concern about Suárez, it’s that his defense seems to have deteriorated. His -4 FRV is a career low, down from 8 in 2023 and 2 last year, though DRS paints a picture of a less dramatic fall-off, from -2 in both 2023 and ’24 to -4 this year. Still, the tradeoff with his offense has been more than worth it. He’ll be a big upgrade on the Mariners’ primary third baseman, rookie Ben Williamson, who has hit for just a 76 wRC+ while supplying visually impressive defense, though his metrics are split on its value (8 DRS, 0 FRV). If the Mariners are worried enough, they have the option to play Williamson at third and DH Suárez instead of Jorge Polanco or Mitch Garver, but I wouldn’t expect that often.

For what it’s worth, while Chase Field is more generally more offense-friendly than T-Mobile Park (101 vs. a major-league low 93 in terms of our basic five-year park factors), T-Mobile has the higher park factor of the two when it comes to righty homers (99 vs. 91). If Suárez merely produces at the level of his last stint in Seattle, he’ll be fine, but he may see an uptick. He joins a team that’s 57-52, tied for second in the AL West with the Rangers, five games behind the Astros; the pair are tied for the third Wild Card spot as well. Seattle’s offense currently ranks sixth in the AL in scoring (4.51 runs per game) and seventh in slugging (.409), but is tied for second in wRC+ (110). Naylor upgraded a position that landed the Mariners on my annual Replacement Level Killers list, so this should become an even stronger lineup.

Suárez was expected to be the biggest bat available ahead of the deadline, drawing interest from the Astros, Brewers, Cubs, Phillies, Red Sox, Reds, Yankees and perhaps others along with the Mariners. It may rate as a disappointment that the package the Diamondbacks received doesn’t include any prospects that cracked either our preseason Top 100 list or the updated one from earlier this week, but that’s the nature of rentals. Locklear placed 21st on the Mariners list in mid-June as a 40-FV prospect but has since been upgraded to a 40+, with Cranton (no. 23) a 40 FV as well (no change) and Burgos missing the list but getting an honorable mention in the “Good Breaking Stuff” section; he’s since been upgraded to a 40 FV.

Of course, each is worth a closer look. Locklear, a 6-foot-2, 210-pound righty first baseman, was the Mariners’ second-round pick in 2022 out of Virginia Commonwealth and signed for a $1,276,500 bonus. He made his major league debut with a 16-game midseason cup of coffee last year, but struggled mightily (.156/.224/.311, 58 wRC+). This year at Triple-A Tacoma, he hit .316/.401/.542 (136 wRC+) with 19 homers and a 21.9% strikeout rate, down about three points from last year’s mark thanks to some key mechanical changes. Here’s what Eric has to say about him in his most recent update:

Locklear cruised through the minors with some visual cues that indicated he might not keep hitting against big league stuff. He had a brief 16-game debut in 2024 during which he struck out in 20 of his 45 at-bats. In 2025, Locklear has made substantive changes to his swing and is a much different hitter. Last year, he was more geared to pull in the extreme, except the length of his swing only allowed him to be on time to pull breaking balls. He swung underneath a ton of fastballs and posted a 66% contact rate, basically unplayable for all but the strongest of power-hitting first basemen. This year, his hands have come down; they’re starting and loading in his gut/chest area instead of up around his head and chin. This seems to be working better for Locklear, whose contact profile is a little more balanced now (he still can’t pull fastballs in the air at all, but the way he sprays sliders has totally changed), and his contact rate has risen to a more respectable (but still not great) 71%. He does basically all of his damage against pitches in the heart of the zone; he’s not nearly as dangerous when you successfully locate away from him. It’s definitely a skill set that fits in the bottom half of the first base player population, but a year ago it looked like Locklear’s offensive output might not be viable at all.

Seasoning this is Locklear’s defense, which is excellent. He’s comfortable navigating foul pops, makes accurate throws to the other bases, and executes tough feeds to his pitchers when they have to cover. He should be a nice righty-hitting complement to Pavin Smith and Adrian Del Castillo, and also can play a pinch-hit role similar to the one Randal Grichuk was playing before he got traded.

The Mariners recalled Locklear on Wednesday, but he didn’t play for them. With Naylor gone and Smith on the injured list due to an oblique strain, he figures to get an immediate look in Arizona.

Cranton is a 6-foot-3, 215-pound righty whom the Mariners drafted in the third round last year out of the University of Kansas. He has just 18.1 innings of professional experience under his belt, including 10 this year, because he was concussed by a comebacker on March 7 and didn’t make his season debut until June 24. After two appearances at the team’s Arizona Complex League affiliate, he joined High-A Everett, where he’s posted a 36.7% strikeout rate while allowing one run in eight innings. From Eric’s notes:

Cranton was a California prepster who decommitted from Arizona to pursue the junior college route. After two seasons at Saddleback (he missed one of those due to shoulder surgery), he matriculated to San Diego State and then finally to Kansas for his redshirt junior and senior years. He was one of the most talented seniors available in the 2024 draft, with a fastball regularly in the upper 90s and a hard slider with inconsistent shape. His fastball averaged 97 mph after last year’s draft and featured plus vertical movement. He seemed poised to race to the big leagues, basically as fast as he could polish his 85-88 mph slider, but Cranton was hit in the head by a comebacker on March 7 (his fastball was more 93-95 that day) and dealt with post-concussion symptoms for a while. Cranton’s mid-90s heater, which has uphill angle, gives him one plus weapon, and it may be better than that if he can eventually sustain his peak velo. Whether or not Cranton will have a second devastating weapon will depend on how consistent his slider feel can become; it’s still finishing in several different directions. Cranton looks like a fastball-heavy middle reliever.

The Mariners signed Burgos (who lists at six feet and 185 pounds) out of the Dominican Republic in 2019. Prior to this year, he’d never pitched above High-A, but he rocketed through Double-A Arkansas, where he posted a 0.64 ERA and 27.6% strikeout rate in 28 innings. He’s been on the move since late June, with one appearance at Tacoma, four for the Mariners (4.05 ERA and 2.04 FIP with a 27.6% strikeout rate in 6.2 innings, for what it’s worth) and then three more for Tacoma. Here’s Eric:

Burgos has been on the periphery of the last couple of Mariners prospect lists because he’s been developed as a relief-only guy and none of his pitches have been generating above-average miss or chase. Though that’s continued in 2025 as he’s made his big league debut, Burgos’ deceptive arm speed, and the way his pitches split the plate like the forked tongue of a snake, keep him off the barrel. He has a mid-90s sinker and a mid-80s sweeper, with a low-90s cutter in between the two of them. A fantastic athlete for his size, Burgos’ delivery is direct toward the plate and he throws a ton of strikes, they’re just often in the meat of the zone. His pure stuff is better than the miss/chase results Burgos has been able to get the last couple of years. There are even those in baseball who think Burgos is a candidate to be stretched out as a grounder-getting starter thanks to his repertoire depth and athleticism. He should contribute to Arizona’s bullpen right away in a middle-inning capacity.

With the departure of Suárez, the Diamondbacks figure to give top prospect Jordan Lawlar, their 2021 first-round pick, a look at third base, but not immediately, as he’s still recovering from a June 15 strain of his left hamstring, suffered while playing at Triple-A Reno. The 23-year-old Lawler is a 55-FV prospect who’s currently 10th on The Board. He was raking at Reno (.319/.410/.583, 136 wRC+, 10 HR, 18 SB), but went 0-for-19 with a walk during an eight-game stint with the Diamondbacks in late May. Though naturally a shortstop, he’s been blocked there by Geraldo Perdomo and at second base by Ketel Marte, so this would appear to be his big break. That said, he’ll have to allay some concerns about his hit tool (35 PV/40 FV). The development of his hitting has lagged behind the rest of his game amid myriad injuries in the minors (shoulder, rib, hamstring, thumb), and he’s slashed just .080/.179/.080 with 20 strikeouts in 56 PA with the Diamondbacks in 2023 and ‘25.

All told, this is an appropriately aggressive move by the Mariners, who have landed a tried-and-true middle-of-the-lineup bat — perhaps the best to change teams this month — without giving up any prospect central to their future. Along with Naylor and whoever else Seattle lands, Suárez will greatly aid their playoff push. As for the Diamondbacks, they were on the fence as far as the decision to buy or sell until the Naylor deal, and now that they’re 51-58, they’re right to scatter their pending free agents to the four winds and lean into restocking their roster and system for next year. We’ll see what else Thursday brings.