MLB Mock Trade: Cardinals Send 29-Year-Old Star to Diamondbacks

The Cardinals have put together four big trades this offseason, but they might not be done yet...

Apr 4, 2025; Washington, District of Columbia, USA; A detailed view of an Arizona Diamondbacks hat at the game between the Washington Nationals and the Arizona Diamondbacks at Nationals Park. Mandatory Credit: Reggie Hildred-Imagn Images | Reggie Hildred-Imagn Images

The St. Louis Cardinals may have been the most active team in the league during the offseason. They were certainly the most aggressive selling team in baseball.

The Cardinals began their offseason with a pair of trades that sent Sonny Gray and Willson Contreras to the Boston Red Sox. In exchange, the Cardinals landed a haul of prospects including Hunter Dobbins, Richard Fitts, and Brandon Clarke.

They also traded Nolan Arenado in a bit of a salary dump before sending Brendan Donovan to the Seattle Mariners in a monster trade.

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But they might not be done yet. In fact, there's another clear trade candidate on the roster.

Bleacher Report's Zachary Rymer recently suggested the Cardinals should look to trade closer JoJo Romero next and urged the Arizona Diamondbacks to be the team to go after him.

JoJo Romero should be the next trade piece to fall for Cardinals

Feb 16, 2026; Jupiter, FL, USA; St. Louis Cardinals pitcher JoJo Romero throws a pitch during spring training workouts at Roger Dean Stadium. Mandatory Credit: Reinhold Matay-Imagn Images | Reinhold Matay-Imagn Images

"The D-backs did well to bring back Merrill Kelly and to wait out Zac Gallen's market. Their rotation is better for it, but there's still a problem on the pitching side: the bullpen hasn't gotten clear upgrades since posting a 4.82 ERA in 2025," Rymer wrote. "It needs another lefty to pair with Brandyn Garcia, and Romero is the most obviously available one out there. He has a standard-issue lefty reliever skill set, in that he doesn't throw hard but gets plenty of ground balls and limits hard contact."

Romero is the next trade candidate to go. In fact, it's shocking that he hasn't been moved yet, which means the Cardinals might be waiting until midseason to cut ties with him, similar to what they did with Ryan Helsley last year.

The Diamondbacks need to add to the bullpen in a big way and there aren't man yoptions better than Romero on the market. Adding a lefty who could stick in a high leverage role late in games would be the best case scenario in Arizona, especially as they wait for Corbin Burnes to return.

For the Cardinals, it doesn't make sense to hold onto Romero. His contract is running out and he's unlikely to be brought back to St. Louis. The earlier they trade him, the more they'll likely get in return.

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