As the 2025 season approaches, one has to wonder if the Chicago Cubs are done shopping for starting pitching.

The Cubs made a marquee addition to their lineup by acquiring Kyle Tucker from the Houston Astros. But calls from fans for Chicago to add a similar star to the pitching staff have thus far gone unanswered.

There isn’t a slam-dunk ace left on the starting pitching market–except for Japanese sensation Roki Sasaki, who the Cubs have already met with. However, assuming Sasaki goes to one of the favored National League West teams instead, the Cubs may seek a backup plan.

If the Cubs could trade with the Astros for Tucker, why not trade with another American League West team to bring in their next star pitcher?

On Wednesday, Caden Charpentier of FanSided urged the Cubs to swing a blockbuster trade for Seattle Mariners starter Luis Castillo, a three-time All-Star who has been involved in trade discussions all winter.

“Castillo (is) a right-handed pitcher, something Chicago could need to be even more competitive in the NL Central,” Charpentier wrote. “Three out of its top-five starters as of now — Justin Steele, Shota Imanaga and newcomer Matthew Boyd — are all left-handed.”

“The 32-year-old has three years and $72.45 million remaining on his contract with a vesting option for a fourth year at $25 million. Given the kind of money that pitchers have been thrown this offseason, it’s honestly a steal of a contract for the kind of reliability Castillo provides.”

Castillo has excellent strikeout stuff, with 471 punchouts in his two-and-a-half seasons as a Mariner so far, and he’s proven to be as durable as any righty in the game. Those qualities would make him a great fit for the Cubs, who dealt with plenty of pitching injuries last season.

It might not even take top prospects for the Cubs to get Castillo, as the Mariners are mostly looking for big-league-ready bats and salary relief. If Chicago takes on most or all of Castillo’s contract, they might be able to nab him from Seattle without dealing a top-five farmhand.

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