It's tricky, the deadline addition from the buyer's standpoint. You're getting a player expected to play well and improve your contending roster, but the post-deadline stretch drive provides a small sample size for those new faces. As such, aberrant performances – especially for pitchers – are entirely possible. That means even the most headline-grabbing deadline additions are prone to being disappointments across those limited samples. On the other hand, some of those talents procured in the name of improving their new teams' playoff odds and World Series chances do exactly what they were supposed to, sample sizes be damned. Some are even better than expected.
With the 2026 Major League Baseball trade deadline exactly one month behind us, it's time to look back at some of the more notable deals and highlight which headliners have thus far been major successes … or major disappointments. There's still the month of September left to correct or reinforce these performances thus far, but here's where things stand one month out. Bad news first, in keeping with therapeutic best practices …
Deadline disappointments
Padres lead exec AJ Preller correctly identified the rotation as an area of need prior to the deadline, but the Mize addition has not helped the San Diego cause. He's made six starts for the Pads – broken up by an ankle injury in a dugout steps mishap – and over that span he's put up an ERA of 6.97 with an additional five unearned runs on his ledger. From a run-prevention standpoint, he's been one of the worst starting pitchers in baseball since the deadline. He's also seen his strikeout rate collapse from 24.9% before the deal to 12.2% since joining the Padres.
As with all these players, the sample size here is small, but Ward has been a disaster in Seattle so far. Acquired from the Orioles (who now have a better record than Seattle), Ward has slashed a meager .113/.212/.141 with one extra-base hit in 71 at-bats. The Ward the M's traded for had a slash line of .256/.383/.346 with Baltimore, so this has been a cratering and then some. He's also been putting these numbers up as a DH with Seattle.
The 33-year-old veteran right-hander was having a subpar season with Seattle before the trade deadline. The White Sox, though, were betting on Castillo's overall body of work – a very strong body of work for the three-time All-Star. Well, he's been even worse since the trade. After five starts with the South Siders, Castillo has an ERA of 6.45, and he's managed to allow seven home runs in 22 ⅓ innings. Would Castillo crack the playoff roster for the Sox if the postseason began right now? Perhaps not, which isn't what you want from a deadline addition.
The Sox acquired Rutschman from the division-rival O's in order to upgrade the position of catcher, which has been a trouble spot for Boston all season. Thus far, Rutschman has not delivered as hoped. Through 15 games and 59 plate appearances as the Red Sox's primary catcher, Rutschman is slashing .170/.254/.245, which comes to an OPS+ of just 43 – or 57% worse than the league-average hitter on a park-adjusted basis. Boston needs Rutschman to reverse course and find his usual level at the plate if they're going to have a chance of claiming the top wild-card spot in the AL.
Acquired from the division-rival Cardinals at significant cost, May, a pending free agent, has not delivered so far as a Brewer. In five post-trade starts, May has put up an ERA of 6.41 in five trips to the mound since the trade, and he's averaged less than five innings per start over that span. The stuff and underlying fundamentals with the Cardinals were strong, so this is probably just the small sample size at work. As well, the Brewers are a pitching-forward organization – one of the best at such things. Thus far, though, May hasn't been the fortifying addition they hoped he'd be.
Deadline successes
Contending teams are usually hesitant to add a new primary catcher in the middle of the season, but the Rays have been richly rewarded for doing so. In 23 games and 20 starts for Tampa Bay, Hicks has a line of .310/.405/.493 with more walks than strikeouts. Behind the mask, he's been an adept framer with the Rays, and he's been slightly above average at controlling the running game. Given the high level of production from a premium position, Hicks has been one of the most valuable players in the game since the deadline.
The Cubs badly needed some rotation stability coming out of the deadline, and Holmes, acquired from the Mets, has given them that and then some. The 33-year-old right-hander enjoyed a highly successful transition from reliever to starter on the Mets' watch, and since joining the Cubs, he's been better than ever. Through five starts and 29 innings with Chicago, Holmes has a 1.55 ERA with no unearned runs allowed. His strong ground-ball tendencies in front of an exceptional Cubs infield defense – exceptional even with shortstop Dansby Swanson on the injured list – have been a perfect pairing.
Has Skubal been at peak since the blockbuster swap brought him to the back-to-back defending champs? Not quite, but he's been the steady frontline presence the Dodgers were hoping he would be. Over five starts, he's put up a 3.00 ERA and backed it up with a sparkling 2.29 FIP. He's also struck out 30.6% of opposing batters since the trade, which is an elite figure for a starting pitcher. The back-to-back AL Cy Young winner has pitched like an ace in L.A.
Luis García Jr., Yankees
García led the NL in slugging when he was traded from the Nats to the Yanks, and he's kept up the power act in the Bronx. With the Yankees, he's batted .292/.337/.500 with five homers in 26 games. That's an OPS+ of 133 – almost the same as his OPS+ with the Nats this season. It's also a welcome jolt of offense for a lineup that's been without Aaron Judge for quite a long time.
The Guardians rank 29th in MLB in home runs, so they targeted Adell to give them some sorely needed pop in the lineup. While he hasn't set the world ablaze with Cleveland, Adell has indeed given the Guards an injection of thump. In 105 plate appearances for the Guardians, Adell has a SLG of .457 with four homers and seven doubles. That comes to an extra-base hit every 8.4 at-bats. Adell's not all that far removed from a 37-homer campaign in 2025, so we know he's got power.
