Oakland's starting pitching depth has thinned in June, as Rich Hill has also been on the DL since June 9 with a groin strain. Rookies Daniel Mengden and Dillon Overton made their debuts, reliever Andrew Triggs made a spot-start against the Angels, and lefty Eric Surkamp made three starts before being designated for assignment Monday.
Hill, who is scheduled to make a rehab start in Stockton on Monday, could rejoin Manaea in stabilizing the rotation soon. A's starters have rebounded in June, allowing three earned runs or fewer in their last 10 starts, but their 5.04 ERA entering Monday was still fourth highest in the Majors.
Manaea was 2-4 with a 6.02 ERA in nine starts prior to his injury.
• Hill made what's expected to be his first and only rehab start with Class A Advanced Stockton on Monday night, throwing 66 pitches in three-plus innings. Hill allowed one run on four hits and struck out six.
Mark Chiarelli is a reporter for MLB.com based in the Bay Area. This story was not subject to the approval of Major League Baseball or its clubs.