White Sox Mariners Trade From Last Year Has Been A Huge Bust

The White Sox and Seattle Mariners connected on an unexpected trade last February when Chicago sent pitcher Gregory Santos to Seattle in exchange for pitcher Prelander Berroa, outfielder Zach DeLoach, and a Competitive Balance Round B pick in the 2024 draft. A lot has changed over the past year. A trade once seen as a win/win for both teams now appears to be a bust for everyone involved to this point.

Gregory Santos

The White Sox initially acquired Santos in a December 2022 trade with the San Francisco Giants that did not garner much attention at the time. Santos quickly put himself on the map in Chicago. In 60 appearances out of the White Sox bullpen in 2023, Santos pitched to a respectable 3.39 ERA, 2.65 FIP, and 1.30 WHIP while striking out a batter per inning and putting up elite metrics. His impressive performance and other injuries in the White Sox bullpen quickly moved him into high-leverage opportunities. At the time of the trade, the Mariners thought they were getting a dominant reliever for years to come.

Santos’s time in Seattle has been rough, to say the least. A right lat strain and biceps inflammation limited him to only eight appearances last season. And while he seemingly is healthy now, his performance has fallen off a cliff. Santos has an elevated 5.14 ERA and 2.29 WHIP in eight appearances this season. 

Even more startling is his walk-to-strikeout ratio. Santos has walked eight batters without striking out anyone over seven innings pitched. He is among the worst pitchers in generating whiffs this season despite being one of the best in that category in 2023. It has gotten so bad that Seattle optioned him to the minor leagues earlier this week. A once prized trade acquisition, Santos has fallen so far that he will have to earn another opportunity in the big leagues.

Prelander Berroa

Prelander Berroa spent most of the 2024 season with the Triple-A Charlotte Knights, where he struggled mightily. The 25-year-old right-hander lit up a 6.41 ERA and 1.84 WHIP in 43 appearances in the minors. He did fare better with the big league team, however. Berroa ended the season on a high note, pitching to a 3.32 ERA in 17 appearances with the White Sox.

Berroa entered 2025 spring training as one of the favorites for the White Sox closer job. Unfortunately, he got hurt during his first spring training appearance. The team later concluded that he needed Tommy John surgery to address his injury. Berroa will miss all of this season and likely a good chunk of 2026 as well. It is a substantial blow to the team and his personal development. He would have had many opportunities to prove himself in the bullpen this season. His injury prevented that from happening, and it is fair to wonder if his stuff will be the same once he returns.

Zach DeLoach

Zach DeLoach also spent most of the season at the Triple-A level and performed pretty well. The 26-year-old outfielder hit .287 with a .375 on-base percentage, .410 slugging percentage, and .785 OPS in 97 games with the Knights. He also appeared in 22 games with the White Sox big league team but hit just .209 with a .622 OPS in 75 plate appearances over 22 games.

DeLoach was designated for assignment in early February of this year but cleared waivers and was sent back to Triple-A. He has spent the entire 2025 season in Charlotte, hitting just .091 in 11 games. The White Sox outfield situation at the MLB level has been decimated by injury, yet they have bypassed bringing DeLoach back in favor of other options. It is fair to wonder if he will get another opportunity with the White Sox.

Blake Larson

Berroa is not the only pitcher in this trade who got hit with the Tommy John bug. Blake Larson, the left-handed pitcher the White Sox drafted with the Competitive Balance Round B pick acquired in this trade, also went under the knife this past January. The 19-year-old had not even appeared in a professional game before succumbing to injury. 

While Tommy John surgery is no longer considered the career killer it once was, it is still a substantial blow to Larson’s development. Given that he is so young however, he will still have plenty of time to establish himself as he hopes to work up the White Sox farm system.

Final Verdict

A year later, it is safe to say that neither side has won this deal. In fact, it is fair to argue that both teams have lost. The Mariners thought they were getting a stud in the back end of their bullpen, while the White Sox thought they were getting contributors for the future. Neither of those has come to fruition yet. Injuries and lack of production have been the common theme for everyone involved. While it has been a bust for both teams up to this point, the book is far from closed. There is still time for both teams to get what they wanted from this trade.