The Athletics placed reliever Mark Leiter Jr. on the 15-day injured list with a right hip impingement and selected the contract of right-hander Geoff Hartlieb from Triple-A Las Vegas, according to MLB's official transactions feed.
MLB lists Leiter's move as dated June 20, 2026, and retroactive to June 18. The same official feed confirms Hartlieb was selected from the Las Vegas Aviators to the Athletics on June 20.
Leiter Move Opens A Bullpen Spot
MLB Trade Rumors reported the injury first through Martin Gallegos of MLB.com and noted that Hartlieb takes Leiter's spot in the bullpen. With Hartlieb selected, the Athletics' 40-man roster is full.
Leiter, 35, has thrown 29 2/3 innings this season. MLBTR listed his ERA at 4.85 while noting that some underlying indicators, including a 3.00 FIP, have been better than the run-prevention line.
The transaction gives the Athletics at least a short-term gap in the middle innings. The retroactive date means Leiter is technically eligible to return in early July, but the official transaction does not provide a recovery timetable beyond the injured-list placement.
Hartlieb Returns To A Major League Bullpen
Hartlieb, 32, has pitched 82 2/3 major league innings since debuting with the Pittsburgh Pirates in 2019, according to MLBTR. His big league track record includes a 7.95 ERA, a 20.0 percent strikeout rate and a 15.0 percent walk rate.
The Athletics are using Hartlieb as an immediate depth arm rather than making a broader roster reshuffle. MLB's transaction record identifies the move as a contract selection, which means he has been added to the big league roster from Las Vegas.
The injury and selection matter because the Athletics' bullpen has been under pressure. MLBTR listed the group at a 4.91 ERA, tied with the Cincinnati Reds for third-worst in the majors, while also noting a more favorable 4.01 expected ERA.
For now, the verified roster result is straightforward: Leiter moves to the 15-day injured list with a hip issue, and Hartlieb gets the open major league bullpen opportunity.