Both the St. Louis Cardinals and Seattle Mariners failed to make the 2023 postseason. These teams were predicted at the beginning of the year to challenge for their respective division titles and possibly even a World Series Championship. While the Mariners did compete for the division up until the last day of the season, their absence from the postseason definitely stings.
The Cardinals's issues were very apparent throughout the year: an inability to hit with runners in scoring position and a lack of top-end pitching in both the rotation and bullpen. The Mariners, on the other hand, struggled primarily offensively, specifically in regard to their batting average and on-base percentage as a team. The Mariners ranked 22nd in batting average this year and 16th in on-base percentage, both below league average.
Luckily, the Cardinals ranked in the top 13 in each of those categories. Meanwhile, the Cardinals ranked 24th in ERA as a staff (Mariners were 3rd) and 26th in ERA+ (Mariners were 7th). While the Cardinals and Mariners were knotted up in the majority of offensive statistics, this gap in batting average and on-base percentage is noticeable. The Mariners would love some more runners on base for their power hitters in the middle of the lineup.
The Cardinals have one player in particular who could solve those problems: Brendan Donovan. Among position players with at least 350 plate appearances, Brendan Donovan ranks 29th overall with a .284 batting average. That figure would be the best on the Mariners. He ranks 30th with an on-base percentage of .365; that would be second to only J.P. Crawford on the Mariners.
The Cardinals would need to ask for pitching in exchange for Brendan Donovan. The Mariners have that in spades on both their major league roster and their farm system. While players such as Logan Gilbert and George Kirby would take a larger package than just Donovan, Bryan Woo, Bryce Miller, and Emerson Hancock could all be had for Donovan.
The Mariners and Cardinals have swapped strengths in the past (see, Tyler O'Neill). They may both benefit this offseason by filling in holes on their major league rosters. While it would be tough to see a fan favorite in Brendan Donovan be traded, hopefully, the return would make it sting a little less. Let the trades begin!