Richard was making his11th start of the season at home against Los Angeles on Friday. Facing lead off man Mark Ellis, Richard threw one pitch for a ball and then tossed an 86 mph changeup for a strike. Immediately after throwing that second pitch, he walked off the mound toward the dugout. He met with manager Bud Black and trainer Todd Hutcheson at the edge of the field before exiting for the clubhouse. Tim Stauffer replaced him for San Diego.
The 29-year-old lefty is no stranger to shoulder injuries. He underwent arthroscopic surgery in 2011 after straining his shoulder in July. He will have further tests done to determine the extent of this latest injury in the coming days.
Richard has struggled in 2013, with a 7.01 ERA in 52⅔ innings and a record of 2-5.