ARLINGTON -- A night after picking up his 100th career victory with a five-hit shutout against the Rangers, A's right-hander Brett Tomko on Tuesday showed up in the visitors' clubhouse moments before batting practice with his right arm in a sling.
As well as he'd thrown the previous night, some assumed he was joking, perhaps using the prop as an excuse for showing up a bit late.
It was no prop. Tomko woke up with discomfort in his arm, got checked by a local doctor and discovered he has a pinched nerve.
"It's in my shoulder," Tomko said after Oakland's 6-1 victory in the second game of a three-game series at Rangers Ballpark. "I felt it a little bit last night, but this morning there was some numbness up and down my arm, so I went and got an MRI."
"He'll be out for a while," A's manager Bob Geren said.
Scheduled to make three more starts this season, Tomko is "definitely" out for Sunday in Oakland against the Indians. Geren said lefty Dana Eveland is an option to replace Tomko in the team's six-man rotation, but calling up a starter from Triple-A Sacramento hasn't been ruled out, either.
Tomko, 37, is 4-1 in six starts since joining the A's in August.
Mychael Urban is a national writer for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.