Revisiting an All-Star Swap

One of my favorite kinds of baseball trade is the one that sends major league talent both ways, between teams ostensibly interested in being competitive, each giving from surpluses to meet immediate needs. It’s certainly the safer option for a front office just to take the passive route and stick with the guys you’ve got, but I appreciate the boldness of swapping a player who’s poised to contribute to your club for one you think might give you more, solve some piece of the positional puzzle, or be able to be a more significant part of your plans down the road.

Such was the case for the Marlins and Twins in January when Luis Arraez (who seems poised to defend his title) was dealt to Miami in exchange for Pablo López and prospects Jose Salas and Byron Chourio. This wasn’t a straight big leaguer-for-big leaguer swap, but both teams were trading for the present. López, 26 at the time, had been the Marlins’ second most productive starter in 2022 and a stalwart of their rotation for the better part of five seasons; the 25-year-old Arraez was coming off a batting title and had been one of the game’s truly elite contact hitters over four seasons of his own. The Twins needed pitching, the Marlins an offensive jolt, and a deal was struck.

If it weren’t a fun enough swap to begin with, it got better when López and Arraez represented their new clubs at the All-Star Game, with Arraez staying true to form with a 2-for-2 night on the winning NL side and López throwing a scoreless ninth inning for the AL. In doing so, the duo became the first pair of players to be dealt for one another and make the next season’s All-Star Game since Josh Hamilton and Edinson Vólquez, who were swapped by the Reds and Rangers in 2007 and emerged as All-Stars the following summer.

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Both players have outperformed their projections this year: López and Arraez currently rank 36th and 37th on the combined WAR leaderboards at 2.74 and 2.72, respectively. The former joined Sonny Gray and Joe Ryan at the top of baseball’s best rotation by WAR, and the latter made a long run at .400 (at .383, he’d have to hit .425 in the 233 at-bats ZiPS projects for him the rest of the way). While there’s so much more involved in this deal, there’s something fun and satisfying about these two players trading places and delivering All-Star first halves with basically equivalent value from opposite sides of the field.

The problem with acquiring experienced young talent is that those players are closer to free agency than you might hope; at the time of the trade, López had two years of team control left to Arraez’ three. Over the remainders of their contracts, ZiPS had projected just 3.7 WAR over López’ two years compared to 7.2 over Arraez’ three. To balance the scales, the Marlins parted ways with a pair of young prospects. Minnesota, meanwhile, solved the team control issue four starts into the season by extending López for $73.5 million through 2027, shoring up a starting pitching unit that risks losing Gray, Kenta Maeda, and the injured Tyler Mahle to free agency after 2023.

As is often the case, we’ll have to wait a while before we understand the full fallout of the deal, but neither prospect has raised his stock since the trade. Salas, a 20-year-old switch-hitting middle infielder with High-A Cedar Rapids, has had trouble cracking the Midwest League, hitting just .175/.267/.259 in 68 games and losing some of his discipline at the plate. Per FanGraphs prospect wizard Eric Longenhagen, his strikeout rate has ballooned to 27.0%, and he’s not doing much damage when he does get the ball in play, though a .224 BABIP may deserve some blame. Though he came into the season ranked 12th among Twins prospects on The Board, this season may sour his outlook if he doesn’t turn it around in the coming weeks. Eric has described him as very physical with above-average bat speed, but his trajectory is making him seem like less of a loss for Miami.

The 18-year-old Chourio, meanwhile, has had limited game action in the FCL due to injury, but he hit .344/.429/.410 in 53 games in the Dominican Summer League last year and has 31 walks compared to 33 strikeouts in 245 pro plate appearances so far. Eric describes him as a strong contact switch-hitter with a shot at developing some more power in time. At 18 years old, he’s a long way from making an impact at the major league level, but he comes in at No. 21 on the Twins list.

While the prospects balanced the scales, it was the specific needs of the major league teams that drove this deal, and it’s been interesting to see how the players’ presences — and their absences — have affected each team this year. For the Marlins, they were dealing from a surplus of capable arms to address a serious need in the lineup. They had a wRC+ of just 88 as a team in 2022, 25th in the majors, and the outlook for 2023 prior to the trade inspired the following level of confidence in Dan Szymborski in his preseason ZiPS projections: “There’s just no realistic scenario in which the offense is a significant plus for the team.”

Enter Arraez, who leads baseball in batting average by 52 points and in OBP by 15 points and ranks sixth in wOBA at .391, both striking out and whiffing a full four percentage points less than any other qualifier. With him leading the way and thanks some welcome contributions from Jorge Soler, Jesús Sánchez, and Bryan De La Cruz, Miami’s offense has been roughly league average by wRC+ even with Jazz Chisholm Jr. missing a big chunk of the first half (and likely even more time in the second half). That’s been enough to earn the Marlins the first Wild Card slot, with a nearly 75% chance of making the playoffs.

The Twins, on the other hand, were rich with infielders. When the chaos of Carlos Correa’s free agency landed him back in Minnesota, he and Jorge Polanco were expected to man the middle infield, as they had for the bulk of 2022, leaving Arraez without a home. But as it turns out, Minnesota’s lineup misses Arraez quite a bit. Polanco has missed time due to injury, as has Royce Lewis, and while rookie Edouard Julien has filled in capably at second, there’s a production hole at third base, where Kyle Farmer and Jose Miranda have underwhelmed in Lewis’ absence.

But if Arraez has exceeded expectations, López has outdone him. At the All-Star Break, he’s already surpassed his full-season ZiPS (2.0) and Steamer (2.5) WAR projections, posting a 3.89 ERA, 3.17 FIP, and 3.44 xFIP in 111 innings. His Baseball Savant percentile rankings are impressive: the top quartile in chase rate (97th percentile), average exit velocity (77th), xBA (84th), xSLG (79th), K% (86th), BB% (76th), and Whiff% (79th). And his consistency in the rotation has allowed Minnesota to withstand injuries to Mahle and Maeda; both were limited to just 12 first-half starts, but the Twins have used only six other starters so far this season thanks in part to López, Gray, and Ryan starting 18 times apiece. Having Arraez around would certainly have helped, but the Twins felt that they had a better shot of replacing his projected production in the infield than they would have trying to match López’ work with thin starting pitching depth.

That is the calculus (or, I guess, the arithmetic) of trading from a surplus to fill a need; López’ and Arraez’ WAR values are nearly identical, but each has accrued that value instead of a generic replacement-level player. In practice, a team deciding between the two has to fill either López’ innings or Arraez’ plate appearances with its own depth and may be more capable of one than the other. Have the Marlins been better off giving López’ starts to Eury Pérez and Bryan Hoeing than giving Arraez’ plate appearances to Garrett Hampson, Jon Berti, and Xavier Edwards? It seems likely, as long as they let Perez pitch some more sometime soon. Are the Twins likely to get more production at the plate from Alex Kirilloff, Donovan Solano, Farmer and Miranda than on the mound from Louie Varland, Simeon Woods Richardson, and the rest of their pitching depth chart? Again, probably, but it’s hard to say. In terms of help on the way, the Twins’ top three prospects on The Board (including Julien) are position players, and four of the Marlins’ top five are pitchers, which may say something about the Twins’ eagerness to commit to a pitcher and the Marlins’ preference for a team-controlled hitter.

Part of what I love about these deals is that they highlight the nuance of baseball trades. It can be a helpful exercise to calculate the projected WAR value on either side of a deal and name a winner, but for a trade like this, it’s also about how the negative space is being filled, and there are far more moving parts involved in answering that question. In any case, these All-Stars were added to their teams to fill acute needs, and they’ve answered the call. Arraez is keeping an otherwise mediocre Marlins offense afloat; López is a part of a trio that could carry the Twins into the postseason. Time will issue a verdict on this deal eventually, but for now, we can celebrate two players thriving in their pursuits to lead new teams to October.