White Sox move struggling Luis Castillo to bullpen

CHICAGO -- White Sox pitcher Luis Castillo will pitch out of the bullpen for the foreseeable future after struggling to a 7.76 ERA in seven outings since Chicago acquired him at the trade deadline.

Castillo, 33, was acquired from the Seattle Mariners in early August, but he hasn't provided needed innings or production for the White Sox, who fell out of first place in the American League Central on Wednesday.

Now, his avenue to potentially help the team will be through the pen.

"We talked to Luis," manager Will Venable said before Thursday night's game against the Detroit Tigers. "The next opportunity for him will be coming out of the bullpen. So we'll look and see what that looks like exactly."

Taking Castillo's spot in the rotation will be rookie David Sandlin, who pitched well Sunday against the St. Louis Cardinals. He'll be on the mound against the Tigers in Game 2 of this series Friday.

Castillo was the headline addition for the White Sox, who were hopeful a change of scenery would be a difference-maker after his rough first half with the Mariners. But things only got worse in Chicago, where he has pitched more than 4.2 innings just once.

Castillo has pitched out of the pen just four times in his 10-year career -- all coming this season when Seattle and Chicago used openers for him. It didn't lead to any success.

The right-hander is owed over $21 million next season, the final year of his contract.

The White Sox enter the final 10 games of their season a half-game behind the first-place Cleveland Guardians in the division. They were in first place from July 4 until Wednesday after losing a series against Cleveland.

The Guardians were off Thursday before opening a home series against the Athletics on Friday.