Strasburg needed only one Minor League rehab start with Double-A Harrisburg, where he allowed one earned run on four hits in five innings with six strikeouts on Wednesday.
In 10 starts before landing on the DL, Strasburg posted a 3-5 record with a 6.55 ERA.
Rookie right-hander Joe Ross was optioned to Triple-A Syracuse to make room on the roster, after filling in admirably for Strasburg.
Ross had a 2.66 ERA with an 11.50 strikeout-to-walk ratio (23 strikeouts, two walks), and he went 2-1 in three starts for the Nats after he was called up from Double-A Harrisburg on June 6.