Orioles right-hander Jason Hammel, making his second start since returning from arthroscopic surgery on his right knee, left Tuesday's game against the Tampa Bay Rays in the fourth inning with an injury to that knee.
After delivering a first-pitch curveball to Rays right fielder Matt Joyce with two outs in the fourth, Hammel limped off the mound after favoring his right leg.
Manager Buck Showalter and head trainer Richie Bancells ran to the mound to check on Hammel, who didn't even throw a warm-up pitch to test the injury.
Hammel, acquired in February from Colorado as part of the trade that sent Jeremy Guthrie to the Rockies, emerged as the Orioles' ace in the first half of the season. He was 8-6 with a 3.46 ERA in 19 starts coming into the night.
Hammel missed nearly eight weeks after surgery on his right knee in mid-July. He had previously had a procedure on his left knee while pitching for the Rays.
Right-hander Steve Johnson replaced Hammel with the Orioles leading 3-1.
On Saturday, the Orioles lost right-fielder Nick Markakis, their top hitter of the second half, for the rest of the regular season. He had successful thumb surgery Tuesday, and the team is optimistic he could return if the Orioles play deep into October.Copyright © 2015, Los Angeles Times