The Oakland Athletics optioned Kendall Graveman to Triple-A Nashville on Thursday.

Graveman took the mound for the A's on Opening Day this season. The 27-year-old has thrown 407 innings (4.11 ERA) dating back to 2015.

He has struggled mightily in 2018. Graveman has allowed 28 earned runs in 28 1/3 innings. No Major League pitcher has allowed more hits or earned runs.

Graveman entered the season on track to hit free agency in 2020.