The Washington Nationals put starting pitcher Ross Detwiler on the 15-day disabled list with a strained right oblique, the Washington Post reported.
He missed his previous scheduled start on May 20 against the Giants and was replaced by Zach Duke. Detwiler's stint on the DL is retroactive to May 16.
Because they had an off day last Thursday, the Nationals were able to move their other starters up one spot. But they will need someone to take Detwiler's place on Tuesday.
Detwiler is 2-4, but has a 2.76 ERA this season.
The Nationals called up 26-year-old Xavier Cedeno from Triple-A Syracuse. He was picked up off waivers from the Houston Astros on April 23.