Chia-Shi Shen, Grant Knipp and Teddy McGraw seem to be on their way to returning to their respective affiliates in the coming months.
SEATTLE — The Seattle Mariners have had better luck with injuries this season compared to last year, at least at the major league level.
The Mariners haven't gone through the first 21 games of the season completely unscathed, however. Right-handed starting pitcher Bryce Miller will begin a rehab assignment Saturday with the Triple-A Tacoma Rainiers after missing the entire year to this point with a left oblique strain.
Utility player Miles Mastrobuoni is also currently on a rehab outing with Tacoma. Other players, outfielder Victor Robles and corner infielder Patrick Wisdom, will continue to be shut down due to a pectoral strain and an oblique strain respectively. Robles was placed on the 10-day injured list April 8 (retroactive to April 7) and Wisdom was placed on the IL on Friday.
Outside of the major league injuries, there's also several intriguing minor league pitchers who have been out the entire year with their own ailments. Here's an update on those three players:
Chia-Shi Shen, RHP (Single-A Inland Empire 66ers)
Shen was a late 2024 international signing by the Mariners out of Taiwan.
The 22-year-old righty made his organizational debut with Seattle's rookie-league Arizona Complex League squad in 2025. He posted a sub-2.00 ERA in seven outings and was promoted to the team's top 30 prospect list (per MLB Pipeline). He's currently ranked as the team's No. 19 prospect.
Shen was promoted to the Single-A Modesto Nuts on June 27 but struggled in his first taste of A-ball. He had a 6.53 ERA and struck out 34 batters in 41.1 innings pitched across six starts with the Nuts. He ended his first year in the minors with a 4.67 ERA and 68 fanned batters in 69.1 innings pitched across 16 outings (12 starts).
Shen began the year on the 60-day injured list. According to Mariners general manager Justin Hollander, the Taiwanese hurler is dealing with a UCL sprain but is expected to be activated sometime in June.
Grant Knipp, TWP (ACL Mariners)
Seattle picked Knipp in the sixth round of the 2024 MLB Draft out of Campbell and he instantly drew attention due to his two-way ability. Knipp is both a right-handed starting pitcher and a hitter. He was a catcher in college, but is going to focus on pitching in pro ball.
Knipp was originally supposed to play in the Mariners Spring Breakout game in 2025. The Spring Breakout game features the respective organization's top prospects.
The 22-year-old was unable to participate in the game due to an injury. The former Camel had to undergo Tommy John surgery, which kept him out the entirety of 2025.
According to Hollander, Knipp's rehab is progressing nicely and he's expected to be activated in June, potentially late May.
Knipp is ranked as the organization's 22nd-best prospect, per MLB Pipeline.
"He threw a bullpen the other day," Hollander said before a game against the Texas Rangers on Friday. "I believe he is set for activation in June. ... He's doing great right now. Both on the pitching side and the position player side. ... He could sneak in there in May. It just depends on if everything goes smoothly."
Teddy McGraw, RHP, (High-A Everett AquaSox)
McGraw, ranked as the team’s 13th-best prospect, boasts some of the best stuff in Seattle's organization but has struggled with injuries.
The former Wake Forest hurler was picked in the third round of the 2023 MLB Draft while he was recovering from his second-ever Tommy John surgery.
McGraw made his pro debut in 2024 and has made 18 appearances (16) starts across the Arizona Complex League, Single-A and High-A since.
The former Demon Deacon had a 3.26 ERA and struck out 24 batters in 19.1 innings pitched across nine appearances (eight starts) with the High-A Everett AquaSox last season.
The Mariners made the decision to move McGraw to the bullpen this offseason and were confident enough to extend him a non-roster invite to major league camp in spring training.
McGraw's injury concerns popped up again and he didn't make an appearance in a Cactus League game due to a biceps injury.
According to Hollander, McGraw threw a live bullpen the other day and is on a scheduled ramp-up plan.
Other notes
-- Roundtable Sports spoke with McGraw and Seattle pitching coach Pete Woodworth on-site at the team's spring training complex in Peoria, Ariz., in March.
-- Roundtable Sports' Brady Farkas spoke with Knipp before the latter's injury in spring training in 2025 in Peoria.
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