Baltimore placed starter Yovani Gallardo on the 15-day disabled with tendinitis Saturday afternoon, according to MASN's Roch Kubatko.
The veteran right-hander left Friday's start with shoulder discomfort. Gallardo told reporters he started feeling the discomfort when he was warming up in bullpen before the game.
The issue might have had a clear affect on his performance. Before departing, Gallardo allowed four runs and five hits.
Gallardo, 30, didn't have much success leading up to his start Friday night, though. Over 18 innings this season, he has pitched to a 7.00 ERA and 3.92 FIP.
Baltimore signed Gallardo to a two-year, $22 million deal in February, but it appeared the Orioles had a desire to sign him for three. The smaller deal was reportedly the result of a shoulder issue that the Orioles were made aware of during his physical.
Bicep and shoulder tendinitis will have Gallardo sidelined for at least two weeks.
In the corresponding roster move, the Orioles activated Brian Matusz from the disabled list. He opened the season on the DL with a back injury and should help Baltimore's bullpen.
Over 49.0 innings last season, Matusz pitched to a 2.94 ERA and 3.58 FIP.
Tyler Wilson is scheduled to start against the Orioles on Saturday night, and Kevin Gausman is set to start Monday.
The Orioles have other options to turn to in Gallardo's absence but they might not prove to be as effective.