Updated at 9:15 p.m.
ORACLE PARK — San Francisco reliever Reyes Moronta left Saturday’s 4-1 loss to the San Diego Padres after throwing just three pitches with what manager Bruce Bochy called an accute right shoulder strain. He will undergo an MRI on Sunday.
“He’s one of our guys, and he’ll be down for sure for a while,” Bochy said. “I don’t want to speculate what’s going on because we don’t know, but he’s a guy that we’ll miss in the bullpen.”
After relieving starter Logan Webb (5.2 IP, 6 H, 7 Ks, 1 BB) with the scored tied at 1-1, a man on second and two outs in the top of the sixth, the hard-throwing right-hander delivered a 2-0, 98-mph fastball to Luis Urias. As Urias fouled the ball off, Moronta fell to the ground, clutching his right arm in pain.
Trainers came out to the mound, as Moronta continued to lay on the turf, and he eventually walked off under his own power, holding his right arm tight to his side.
Moronta has already suffered one major injury, needing Tommy John surgery to reconstruct his right elbow after blowing it out while pitching for the Giants’ Low-A affiliate in Salem-Keizer in 2013. There is no preliminary indication that this injury has any elbow involvement.
In his second full season of major-league work, Moronta has struck out 70 men over 56 2/3 innings with a 2.86 ERA as one of the most effective weapons in what’s been one of the best bullpens in baseball.
Moronta went 5-2 with a 2.49 ERA as a rookie last season, striking out 79 in 65 innings.
Tyler Rogers came on and walked Urias, before getting Austin Hedges to ground out to second to strand both runners, closing the book on both Moronta and Webb, who finished having allowed just one earned run.