Mariners Lose 27-Year-Old Southpaw To Phillies In Free Agency

Seattle's minor-league depth chart took a minor hit

Apr 11, 2025; St. Louis, Missouri, USA; Philadelphia Phillies third baseman Alec Bohm (28) picks up his hat after chasing down a fly ball against the St. Louis Cardinals during the third inning at Busch Stadium. Mandatory Credit: Jeff Curry-Imagn Images | Jeff Curry-Imagn Images

Sometimes, the offseason carousel spins too quickly to catch all the transactions in the moment, especially at the minor-league level.

It's been a winter of heavy turnover for the Seattle Mariners, who saw 29 players elect minor-league free agency in November. Many of those players remain unsigned, but one left-handed pitcher landed with a National League powerhouse for the 2026 season.

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According to his official roster page, lefty Adam Seminaris signed with the Philadelphia Phillies on Nov. 18, though it took at least a week for the transaction to appear on the official transactions log.

Seminaris' brief Mariners stint led to deal with Phillies

Seminaris was a 26-year-old pitching at Double-A this season, so performance isn't the only indicator of whether or not he has a major league future. That said, he performed quite well for the Arkansas Travelers, who play in a league known for offense.

In 24 outings, including 22 starts, Seminaris went 7-7 with a 3.02 ERA. He struck out 105 batters in his 125 1/3 innings and walked only 36. Most impressively at all, he allowed only two home runs, thanks in large part to a 1.19 ground ball to fly ball ratio.

Seminaris briefly reached Triple-A in 2022 and 2023 as a member of the Los Angeles Angels and Milwaukee Brewers organizations. But the Brewers released him at the end of 2024 after spending the entire season in Double-A, so he has to at least be hoping for another step forward this year.

The Phillies initially assigned Seminaris to Triple-A Lehigh Valley, but he won't know for sure where he's beginning the season until the club breaks camp in late March to conclude spring training.

If Seminaris eventually becomes a big-leaguer, the Mariners could regret not making more of an effort to re-sign him at the end of his lone season in the organization. But the story is still far from being written as the former fifth-round draft pick attempts to break through in the minors.

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