Updated

WASHINGTON (Reuters) - Washington Nationals rookie pitcher Stephen Strasburg gave up a career-high six runs on Tuesday in his first start since coming off the disabled list as the Nationals were beaten 8-2 by the Florida Marlins.

The 22-year-old right-hander allowed six runs and six hits in 4-1/3 innings. It was Strasburg's first start since July 21.

Strasburg, who made one of the most talked about major league debuts in years in June, was scratched minutes before his last scheduled start on July 27 because of stiffness in his shoulder while warming up.

"I felt 100 percent. I didn't know (where the pitches) were going today," Strasburg told reporters. "It happens being on the DL, coming back maybe expecting a little too much of myself."

Strasburg struck out just four batters.

"It's been about 19 days since he had been in the ball game, so that's an area where you can find some rust," said Nationals manager Jim Riggleman. "I think he'll put this one behind him and go out and give us a better outing next time."

Florida's Dan Uggla slugged his 26th home run of the season in the first inning off Strasburg and added a two-run double in the third where the Marlins took a 4-0 lead.

Strasburg gave up a RBI double in the fifth and was replaced.

Pitcher Anibal Sanchez (9-7) picked up the victory allowing two runs and striking out seven batters in 6-2/3 innings.

Florida shortstop Hanley Ramirez finished 3-for-4 with three runs.

(Reporting by Jahmal Corner in Los Angeles; Editing by Greg Stutchbury)