Philadelphia Phillies
The Phillies currently employ Alec Bohm, a 2024 All-Star, at third base, but they're reportedly open to moving him to shake up the roster. Arenado would join a talented veteran group that includes Bryce Harper, Kyle Schwarber, JT Realmuto, Aaron Nola, and Zach Wheeler in Philly, and he wouldn't have to be the primary offensive producer with the Phillies. That would bode well for his career.
The Phillies have a decent farm system, as they currently have four players in MLB Pipeline's top-100 prospect list. If the Cardinals chip in some money with Arenado, perhaps St. Louis could land a top prospect from the Phillies. They could also swing a deal for Alec Bohm, though that would create a logjam in the infield between Bohm, Nolan Gorman, Brendan Donovan, and even Thomas Saggese.
Cardinals receive: RHP Jean Cabrera, RHP Seth Johnson
Phillies receive: 3B Nolan Arenado, $10 million
In this scenario, the Phillies flip Alec Bohm somewhere else to open space for Arenado. The Cardinals also send some money to offset Arenado's contract.
In Cabrera and Johnson, the Cardinals get two pitchers who are near MLB-ready and have solid floors. Cabrera finished 2024 with a 3.80 ERA between high-A and Double-A with 110 strikeouts in 106.2 innings. He has a strong fastball-changeup combination, and with some physical growth, he could evolve into a good reliever.
Johnson uses a 60-grade fastball and an elusive slider to get batters out. The 26-year-old righty has already made his major-league debut, and he had a 2.73 ERA in the minors last year through 95.2 innings.
New York Mets
The Mets just got the offseason's prized player in Juan Soto, they've already bolstered their rotation, and they may not be done just yet. At the moment, Brett Baty is listed as the Mets' third baseman in 2025, but he had a tough year at the plate in 2024. His defense isn't anything to write home about, either. Arenado would be a significant upgrade at the hot corner for the Mets.
The Mets will surely be contenders in 2025, and Arenado will take them to another level. His plus defense paired with Lindor's at shortstop would give New York one of the best left sides of the infield in the game. If the Mets are unable to re-sign Pete Alonso, they could pivot to the trade market to fill out their corner infield spots.
Cardinals receive: RHP Jonah Tong
Mets receive: 3B Nolan Arenado, $15 million
This isn't the flashiest of trades, but the Cardinals get a legitimate pitching prospect in Jonah Tong. Tong, 21, has a 65-grade fastball that can hit 97 MPH with nearly 21 inches of induced vertical break. He pitched in low-A, high-A, and Double-A last year, and he finished with a 3.03 ERA in 113 innings. He also struck out 160 batters while holding them to a .204 batting average. He walked only 47 batters, too. Tong is a serious pitching prospect, and he would provide even greater depth behind guys like Quinn Mathews and Tink Hence.
The Cardinals kick in some cash to make Arenado's contract manageable, and the Mets form a potent corner infield combination of Nolan Arenado and Mark Vientos.