Luis Castillo’s disastrous stretch has now cost him his spot in the Chicago White Sox rotation, as Chris Getz’s marquee trade deadline acquisition has taken another step in the wrong direction.
Adding insult to injury, Boston Smith, the organization’s No. 15 prospect at the time he was dealt to Seattle in the Castillo trade, finished the minor league season with 31 home runs and a .990 OPS. Meanwhile, Seranthony Domínguez has settled into the Mariners’ bullpen, posting a serviceable 3.72 ERA since joining Seattle.
The package the White Sox gave up for Castillo isn’t necessarily the issue; it’s the thought process behind the trade.
Chicago was in the midst of an enchanted season, with the American League seemingly there for the taking. A few aggressive moves at the deadline could have given the White Sox the reinforcements needed to make a legitimate World Series push. Instead, Chris Getz largely did the bare minimum, attempting to address the team’s holes with fliers and change-of-scenery candidates. That approach has now come back to bite the White Sox.
Entering Friday, Chicago was just 19-22 since the trade deadline, with Castillo’s inability to consistently work deep into games emerging as a major factor.
Leading up to the deadline, reports indicated the White Sox were willing to absorb salary in exchange for a pitcher with multiple years of control, but were unwilling to part with any of their top prospects.
That significantly narrowed Chicago’s options on the pitching market. While Castillo checked the boxes for club control and a relatively modest prospect price, he also came with plenty of red flags.
His strikeout rate, once one of the strengths of his game, had fallen significantly to just 19%. He was also struggling to keep the ball on the ground, with his average exit velocity, barrel rate, and ground-ball rate all ranking in the bottom half of MLB — concerns that were only amplified in a hitter-friendly environment like Rate Field.
Castillo had also largely abandoned his changeup, once one of his most lethal weapons. The White Sox have tried to help him reestablish the pitch, but those efforts have been largely unsuccessful to this point. Outside of a seven-inning, one-run outing against Cincinnati, Castillo has struggled to consistently give Chicago the length it needed from its rotation.
In his first six starts in a White Sox uniform, Castillo made it through the fourth inning just twice and pitched beyond the fifth only once. When Will Venable turned to an opener strategy for Castillo in his most recent outing in St. Louis, the results were no better. Castillo surrendered three runs on four hits and three walks while recording just eight outs over 2.2 innings.
At this point, it’s fair to wonder whether Castillo should even be on the playoff roster. His ERA has ballooned to 5.67 on the season, while his .456 expected slugging percentage allowed ranks in the bottom 10% of MLB.
He can no longer be relied upon as a starter because of his inability to consistently work deep into games — a quality that had been one of his calling cards throughout his career. But even a move to the bullpen hasn’t provided much reason for optimism.
Castillo owns a 5.57 ERA across 23 starts this season, and his numbers have actually been worse in relief, where he has posted a 6.43 ERA over 14 innings. While that sample is considerably smaller, it does little to suggest he has found a viable role for Chicago.
But this isn’t a problem that will simply go away. The White Sox are on the hook for $22.75 million of Castillo’s contract in 2027, a steep price to pay for a fifth starter or bulk reliever.
On paper, the idea made sense given Castillo’s track record.
But at the time of the trade, I wrote that if more moves were coming, the risk would be much easier to justify. If not, the White Sox risked overpaying for a pitcher who would only marginally improve their postseason chances.
Those fears have now come to fruition. Chicago did not make any other significant additions, instead rolling the dice on a pitcher who was already in the midst of the worst season of his career. Making Castillo the centerpiece of the trade deadline ultimately felt like a missed opportunity for Chris Getz to make a meaningful upgrade to the roster.
If the White Sox ultimately miss the playoffs or get bounced in the Wild Card round, the Castillo trade will be one of the biggest missed opportunities of Getz’s tenure — particularly because it came at a time when Chicago had a legitimate chance to make a deeper postseason run.
