5 starting pitchers the Cardinals could trade for to rejuvenate their rotation

RHP Mitch Keller, Pittsburgh Pirates

Intradivisional trades of this magnitude don't happen often, but when timelines, needs, and the market align, they can happen. The more and more I think about it, the more I can see Mitch Keller being a fit for the Cardinals, and the Cardinals having a compelling offer for the Pittsburgh Pirates.

Keller, 29, is under contract with the Pirates through the 2028 season, and is set to make about $17 million in 2026, $18.5 million in 2027, and $20.5 million in 2028. Keller has been worth between $16.7 million and $25.8 million per season since 2022, and is one of the more underrated starters in the game today.

Keller certainly isn't a number one starter, but likely profiles as more of a really good number three who adds more value due to the innings he is able to eat along the way as well. He's not flashy, but he is good, and this certainly isn't another Miles Mikolas, Erick Fedde, or Kyle Gibson situation.

Keller's 4.51 ERA for his career won't thrill anyone, but since 2022, that ERA sits at 4.15 with a 3.94 FIP and 3.98 xFIP while averaging 176.8 innings per season and 31 starts. Really solid production that is consistent and durable is not easy to find in today's game. Keller would provide the Cardinals with a steady option for their rotation over the next three seasons, who will be making substantial but manageable money during that time.

The Pirates, who need to try and improve with Paul Skenes' team-control dwindling, need a major boost to their offense and could seek to find some bats from St. Louis in return for Keller. In 2025, Pittsburgh ranked dead last in runs scored and slugging percentage and bottom three in batting average and wRC+.

Perhaps someone like Nootbaar or Gorman could be a part of this conversation, along with a little bit of prospect capital? Or maybe an upside position player prospect like Jesus Baez or Ryan Mitchell could headline the conversation? If Keller was not on a substantial contract already, I think Pittsburgh could get a lot more, but the money he's due over the next few seasons is not cheap, and he's good, but not great.