FanGraphs' playoff report card highlights where Mariners' Dan Wilson must improve

Dan Wilson took up the mantle as manager of the Mariners in tumultuous times. After the team's second-half slump in 2024, Scott Servais was unceremoniously fired after nine years. Initially, the appointment of Wilson seemed more like fan service than an actual move to improve the team, but after a 21-13 record to finish the season, it turned out that he might actually have what it takes to be a solid manager. He received high praise from players and reporters alike and seemed like the right man to lead the Mariners in 2025.

Wilson's first full season was, in many ways, a rousing success. It ultimately came to an end in a competitive seven-game ALCS against the Toronto Blue Jays, which gave us enough data to scrutinize in the name of accurately assessing his strengths and weaknesses as a big league manager. Based on this data, Ben Clemens of FanGraphs wrote a very detailed report card of Wilson's decision-making and the results are what you might expect.

Despite making strong decisions with the lineup, Wilson's management of his pitching staff was a critical point of weakness

Clemens points out that managing a lineup with five players that had regular season OPS+ figures greater than 125 isn't the hardest job in the world, and only requires changes to be made to the bottom of the lineup and in specific pinch-hitting situations. Wilson had some creative moments, notably calling on the switch-hitting Leo Rivas to face Tigers lefty Tyler Holton in ALDS Game 5, a decision that paid off with a game-tying single.

However, it was a very different story when it came to managing the arms. To Wilson's credit, Seattle's rotation underperformed expectations, especially George Kirby who pitched to a 6.00 ERA in his four starts. Logan Gilbert and Luis Castillo had better numbers but ultimately, the Mariners' downfall was the lack of length and overreliance on the bullpen.

Even when faced with inefficient outings and high pitch counts that may have forced his hand, Wilson could've placed more trust in his starters to give him a few more crucial outs. It's also true that a mismanagement of his best relievers in blowouts like games 2, 3, and 4 expended valuable arms in low-leverage situations, making them unavailable when it mattered most.

This all came to a head in the final game of the Championship Series when Wilson decided to deploy Eduard Bazardo instead of Matt Brash or Andrés Muñoz in the seventh inning, a decision that would become one of his most controversial. This ultimately allowed George Springer to hit a three-run homer that sealed Seattle's fate. Funnily enough, he was named the AL Manager of the Year by The Sporting News shortly after.

Was this the result of inexperience, or was Wilson simply saving his best arms for what he believed to be an inevitable trip to the World Series? It's difficult to say for sure, but this outcome was ultimately the result of small management inefficiencies that accumulated over time.

Does his performance within a sample of 12 postseason games trump what he accomplished during a full season of 162? Probably not on paper, but when factoring in the sheer importance of playoff games vs. regular season games, it taints the perception of an otherwise successful year. Nonetheless, Wilson is early on in his managerial career and has plenty of lessons left to learn. He has already demonstrated that he can lead the Mariners to the playoffs. Now he just needs to prove that he can lead them through it.