A's Calling Up Former Kansas City Royals Prospect For MLB Debut

Following the diagnosis of a Grade 1 flexor strain for Jacob Lopez on Monday, the A's officially placed the left-hander on the IL on Tuesday. Taking his place on the roster will be former Kansas City Royals prospect Mason Barnett, whom the Athletics acquired at the 2024 MLB Trade Deadline as part of the return for Lucas Erceg. Barnett is ranked as the A's No. 11 prospect by MLB.com.

Barnett had not been on the A's 40-man roster before the move, but to make room for Zack Gelof on the roster yesterday, they decided to designate Luis Urías for assignment, which left them with 39 players on the 40-man roster, essentially clearing up a spot for Barnett.

With Barnett, 24, needing to be on the 40-man roster ahead of the Rule 5 Draft this winter anyway, he was going to be added to the roster in the coming weeks regardless.

After coming over from the Royals last season, Barnett improved his strikeout rate from 27.4% to 31.1%, and knocked his walk rate down to 7.8% from nine. That helped lead to his ERA going from a 4.91 in 91 2/3 innings with the Royals, to a 2.61 ERA in 41 1/3 innings with the A's. That said, his FIP was roughly similar between the two Double-A stops, sitting at 3.68 with K.C. and 3.24 with the A's.

Barnett has spent the entire season at Triple-A Las Vegas and is 6-2 with a 6.13 ERA and .801 opponents OPS in 25 games, 23 starts, in his Triple-A debut.  He has struck out 124 batters in 119.0 innings (9.38 per nine innings), but has also walked 65 (4.92 per nine innings).

The 24-year-old right-hander leads the Pacific Coast League in games started and ranks second in strikeouts and innings pitched. Barnett was originally selected by Kansas City in the third round of the 2022 First-Year Player Draft and was traded to the A’s on July 30, 2024 with Will Klein and Jared Dickey in the Erceg deal. Klein was DFA'd in January, and is now with the Los Angeles Dodgers.

Barnett is 22-17 with a 4.44 ERA in 78 games, including 72 starts, in four seasons in the minors. 

His role with the club has not been announced just yet, but the A's do need to fill one spot in the rotation. With Osvaldo Bido getting the ball to begin Tuesday night's game, they still have Joey Estes ready to go out of the bullpen as a potential starting option, if needed. Of course, Barnett is also an option for the club in that role too.

That decision could ultimately come down to how the next couple of days go and how many arms the team needs to use in relief.