The 27-year-old is a free agent in the offseason, so he's a prime candidate to possibly move before the trade deadline.
The Tigers are last in the American League Central at 29-65 and in the middle of a complete teardown. Detroit could hold on to him for the remainder of the year and collect a compensation pick were he to decline a qualifying offer and sign elsewhere. Flipping him for a prospect or two would make just as much sense.
Detroit should benefit from what is a general dearth of realistic options for teams hoping to improve ahead of the stretch run.
USA Today's Bob Nightengale reported Kansas City Royals second baseman and right fielder Whit Merrifield is unlikely to move based on the Royals' high demands. In addition, the Chicago White Sox prefer to re-sign impending free-agent Jose Abreu rather than trade him.
With home run totals climbing across the league, Castellanos' total is a little underwhelming. His performance could be hindered somewhat about the general uncertainty regarding his future.
"This, probably, in its own way, has been the most difficult year I've had, just with everything that's gone on," he said, per McCosky. "It's just a learning experience. All I can do is show these guys (his teammates) that you've got to go out and play every day and do what you can to help the team."
As Bastian outlined, the Cubs have an obvious need to get a right-handed bat in a corner outfield position. He'd be an offensive upgrade over Albert Almora Jr., with Jason Heyward going from right to center.
If Chicago doesn't give the Tigers the trade offer they're looking for, another team is likely to swing a deal for Castellanos prior to July 31.