SEATTLE – The Mariners added some pitching depth and versatility to their 40-man roster, making a small trade Friday afternoon with the New York Mets.
Seattle acquired right-hander Cooper Criswell from New York in exchange for cash considerations. To make room for Criswell on the 40-man roster, left-hander Jhonathan Diaz was designated for assignment.
Criswell, 29, was designated for assignment by the Mets two days earlier to clear 40-man roster space for the four-player trade between New York and Milwaukee that sent All-Star right-hander Freddy Peralta and right-handed pitcher Tobias Myers to the Mets in exchange for a pair of prospects.
It was the second time Criswell was designated for assignment this offseason. After pitching for the Red Sox the past two seasons, he was designated for assignment Dec. 4 when Boston made a five-player trade with the Pirates.
Criswell rode the shuttle between Boston and Triple-A Worcester in 2025. He appeared in seven games — six relief appearances and one start — for the Red Sox, posting a 1-0 record with a 3.57 ERA. He made 14 starts and two relief appearances for Worcester, going 4-2 with a 3.70 ERA.
He pitched extensively for the Red Sox in 2024, appearing in 26 games — 18 starts and eight relief appearances — with a 6-5 record and 4.08 ERA.
Criswell’s comfort level to pitch as a starter and a reliever is a plus for Seattle. He is out of minor-league options, which could play a factor in his role and spring training buildup with the Mariners.
Diaz, 29, pitched in one game with the Mariners in 2025. He made 26 starts and one relief appearance for Triple-A Tacoma, leading the Pacific Coast League in starts with a 4.15 ERA (64 ER, 138.2 IP).
Also
Utility player Samad Taylor, who was designated for assignment earlier this week, has declined an outright assignment to the Mariners’ minor-league system and has opted to become a free agent.
FanFest sells out
The Mariners announced that FanFest, which returns after a long hiatus, is sold out.
“It’s incredible to see the passion and excitement from our fans heading into the 2026 season,” said Mandy Sundblad, Mariners vice president of marketing and fan engagement. “We finished the 2025 season with nine consecutive sellouts at T-Mobile Park, and it’s great to see the momentum carry over to 2026 with unprecedented crowds at FanFest. Opening day is right around the corner on March 26 and we can’t wait to welcome the team back home to a packed house.”