The Seattle Mariners may not have much left to play for in the standings, but they did manage to pull off one tidy bit of business at the trade deadline.
Right-hander Luis Castillo, dealt from Seattle to the Chicago White Sox before the August 1 deadline, is still owed $21.6 million in 2027. Given how things have gone since the move, the Mariners may have done well to get out from under that deal when they did.
Castillo has been hit hard with Chicago, posting a 7.76 ERA in 29 innings. He has allowed 41 hits, including eight home runs, over that stretch.
Bleacher Report’s Kerry Miller pointed to Castillo as the player who has delivered the worst value to Seattle in 2026, while making clear that Cal Raleigh was not the answer.
"If you were expecting Cal Raleigh here, you've slept through the part where he has a 1.200 OPS over his last 18 games. His resurgence has done nothing to help salvage Seattle's dreadful record, but at least he has turned things around," Bleacher Report's Kerry Miller wrote about not picking Raleigh as the player who's provided the worst value to Seattle in 2026.
"Castillo never did, and it's a small miracle that the M's managed to trade him (and what's left on his contract) to Chicago ahead of the deadline," Miller added.
That assessment lines up with how Castillo was pitching before the deal, too. The 33-year-old had a 5.06 ERA with the Mariners and struck out fewer than eight batters per nine innings across 99.2 innings.
So while Seattle’s season has gone nowhere fast, the front office deserves credit for getting Castillo’s contract off the books. The White Sox needed help in the rotation, but this is the kind of move that could end up costing them.
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