What Seth Johnson Surgery Means for Athletics Going Forward

The A's were absolutely killed by injuries over the course of the 2026 season, and it seems like the injuries are starting to spill into the offseason.

One of the club's only trades last season was sending outfielder Colby Thomas to the Philadelphia Phillies in a buzzer-beating trade on deadline day. In the deal, the A's landed right-hander Seth Johnson.

Jun 13, 2026; Summerlin, Nevada, USA; Athletics third baseman Zack Gelof (20) celebrates with right fielder Colby Thomas (32) after scoring against the Colorado Rockies during the sixth inning at the Las Vegas Ballpark. Mandatory Credit: Lucas Peltier-Imagn Images | IMAGN IMAGES via Reuters Connect

The A's gave Johnson some big-league opportunities over the last two months of the season because other pitchers were injured. A couple of arms like Jack Perkins had to slide into the rotation because of injuries to key players like Luis Severino and JT Ginn.

However, it looks like even Seth Johnson sustained an injury of his own, which has now required him to undergo surgery.

Seth Johnson Undergoes Knee Surgery Following 2026 Season

Sep 22, 2026; West Sacramento, California, USA; Athletics pitcher Seth Johnson (52) throws a pitch against the Los Angeles Angels during the fourth inning at Sutter Health Park. Mandatory Credit: Ed Szczepanski-Imagn Images | IMAGN IMAGES via Reuters Connect

Since the A's are not playing October baseball this year, the team is done, and players are taking care of their bodies to be ready for Spring Training. The upcoming MLB lockout could delay Spring Training and even the season.

Even without the delay, Seth Johnson is expected to return for Spring Training following his knee surgery.

A’s news: Seth Johnson underwent successful left knee surgery today at Stanford Orthopaedic Hospital. He is expected to be ready for Spring Training.
— Martín Gallegos (@MartinJGallegos) October 5, 2026

His surgery was completed on Monday, Oct. 5 at the Stanford Orthopaedic Hospital. His left knee was the issue, and now the right-hander will start rehab to build up over the next few months.

Since it is the offseason, there's no rush to return to activities, so Johnson can take his time and still be ready to go whenever A's baseball returns after the lockout.

Johnson's Potential Makes Him Breakout Candidate in 2027

Sep 12, 2026; West Sacramento, California, USA; Athletics pitcher Seth Johnson (52) throws a pitch against the Seattle Mariners during the third inning at Sutter Health Park. Mandatory Credit: Dennis Lee-Imagn Images | IMAGN IMAGES via Reuters Connect

Since the A's got their hands on the former first-rounder, Seth Johnson hasn't been super productive, but he has shown some flashes of being a reliable arm.

Johnson has an electric fastball that sits around 97 miles per hour, which puts him in the 90th percentile of all pitchers. His extension is only 6.4 feet, which puts him in the 44th percentile this season.

The 10 fastest pitches thrown by Phillies Pitchers this spring:

99.9- Seth Johnson 2/21
99.3- Seth Johnson 2/21
99.1- Seth Johnson 2/24
98.9- Seth Johnson 2/21
98.9- Seth Johnson 2/24
98.9- Seth Johnson 2/24
98.8- Seth Johnson 2/21
98.7- Seth Johnson 2/21
98.4- Seth Johnson… pic.twitter.com/FwxNyMtlb6
— Phillies Tailgate (@PhilsTailgate) February 24, 2026

If Johnson can get more extension, he could make the ball come in quicker to opposing hitters, and it could potentially help generate weaker contact. Opponents hit grounders just 37.5% against him this season and had a rough hard-hit percentage of 43.8%.

Even though his 5.88 ERA doesn't look great, there's still hope for him to improve next season, as he already has the stuff. A few minor tweaks could turn him into a big piece of the A's bullpen.

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