Fiers (elbow) signed a contract March 24 with Leones de Yucatan of the Mexican League.

Fiers (elbow) suffered a setback during his rehab assignment and is unlikely to return this season, Martin Gallegos of MLB.com reports.

Fiers (elbow) was sharp over 34 pitches in his rehab appearance for Triple-A Las Vegas on Saturday, the team's official site reports.

Fiers (elbow) will make a rehab appearance at Triple-A Las Vegas on Saturday, Matt Kawahara of the San Francisco Chronicle reports.

Fiers (elbow) allowed three earned runs on three hits and a walk over 1.2 innings in Triple-A Las Vegas' loss to Reno on Tuesday. He struck out two.

Fiers (elbow) will make a rehab start for Triple-A Las Vegas on Tuesday, Matt Kawahara of the San Francisco Chronicle reports.

Fiers (elbow) will make a rehab start with Triple-A Las Vegas next week and could return before the end of the season, Martin Gallegos of MLB.com reports.

Fiers (elbow) will throw against hitters Friday, Matt Kawahara of the San Francisco Chronicle reports.

Fiers (elbow) threw a 20-pitch, all-fastballs bullpen session Friday, the Associated Press reports.

Fiers (elbow) is slated to throw a bullpen session Friday, the Associated Press reports.