Red Sox still in market for pitcher, reportedly working to acquire Mariners starter

Luis Castillo has been linked as a possible trade target for the Red Sox. (AP Photo/Matt Freed)The Red Sox added a potential ace to their starting rotation on Wednesday by acquiring Garrett Crochet in a blockbuster deal with the White Sox.

But Boston may not be done when it comes to bolstering their pitching corps with top-end talent.

Speaking to reporters at MLB’s Winter Meetings in Dallas, Red Sox chief baseball officer Craig Breslow stressed that Boston remains focused on adding to a rotation, even with Crochet now in the fold.

“We came here a few days ago thinking we needed to improve our rotation,” Breslow said. “If we exclusively look down one path, we would be closed off from other…