CHICAGO (AP) -- Detroit Tigers right-hander Jordan Zimmermann is expected to be sidelined for up to a month because of a sprained ulnar collateral ligament in his pitching elbow.
Tigers head athletic trainer Doug Teter said Friday that Zimmermann won't be allowed to throw for five to seven days. The righty had an MRI in Chicago on Friday that revealed "some damage to the ligament itself," Teter said.
"Best-base scenario we're in that three- to four-week range right now, is where we would like to be," Teter said. "With that being said, if he needs more time, we're going to take the time we need to get this done right."
Zimmermann left Thursday night's game in Boston before the bottom of the fourth inning with elbow discomfort and was put on the 10-day injured list Friday. The 32-year-old allowed five runs on five hits and three walks as he lost his fourth straight decision, dropping to 0-4 with a 5.93 ERA in six starts. He has a 10.26 ERA in his last four appearances.
Ziimmermann underwent Tommy John surgery in August 2009. He led the National League with 19 wins for Washington in 2013, his first All-Star season.
"I was a little concerned going into the MRI today, and it came back probably the best-case scenario," Zimmermann said. "Something we're going to rehab and take day-by-day and see where it goes."
Detroit recalled right-hander Zac Reininger from Triple-A Toledo before Friday's series opener at the Chicago White Sox.
Reininger, 26, has made one appearance with the Tigers this season, getting one out Tuesday in a 4-2 win at Boston. He was 1-0 with a 0.90 ERA at Toledo in six games and 10 innings.
