Strasburg has been dealing with elbow inflammation over his last few games but would still pitch if it were an important situation such as the playoffs, a source told the New York Post's Joel Sherman.
Washington hasn't announced how long they expect Strasburg to be out of action, but they're cautiously optimistic he'll be able to return in two weeks, Bob Nightengale of USA Today reports.
The 28-year-old hits the DL for the second time this season, after being handed the worst loss of his career in his last outing against the Colorado Rockies, allowing nine earned runs over 1 2/3 innings.
Any sort of injury to Strasburg's throwing elbow is a concerning one for the Nationals, as the hurler underwent Tommy John surgery in 2010.
Strasburg is in the midst of a tremendous season, posting a 15-4 record with a 3.59 ERA and a 11.1 strikeout rate.