"That's the kind of club we've got up and down the lineup," manager Davey Johnson said. "Desi's been huge all year. I was a little upset with Perez [stealing third]; he didn't have the green light. But [third-base coach] Bo [Porter] talked to him."
The Cardinals made it a one-run game, however, in the eighth, when Tony Cruz doubled to left-center field off Ryan Mattheus to drive in David Freese.
The Nationals improved to 81-52, matching the most wins by the franchise since it moved to Washington in 2005. That club finished with 81 wins.
In the National League East race, Washington is 6 1/2 games ahead of Atlanta, which beat Philadelphia, 8-7, on Sunday.
Washington's Stephen Strasburg pitched six shutout innings, allowed two hits and struck out nine to raise his total to a National League-leading 195 whiffs in 156 1/3 innings. After having Tommy John surgery in late 2010 and coming back from the procedure late last year, Strasburg is on an innings limit in 2012. He is expected to pitch between 160 to 180 innings this year.
Strasburg's last game will be Sept. 12 against the Mets at Citi Field, according to Davey Johnson The plan to shut shut down Strasburg has been in place since last year.
Johnson said the team has faced adversity all year because of injuries and will survive without Strasburg.
"I think two starts [for Strasburg]," the manager said. "Unless I let him pitch 10 [innings] the next one out, which I'm not going to. So I think his last start will be on the 12th. We've faced adversity all year long. I mean, we didn't have our cleanup hitter [Michael Morse], we didn't have our closer [Drew Storen]. We lost our starting catcher [Wilson Ramos], we lost Jayson Werth for two months.
"I mean, that's the way this year has been. We've been fortunate in the starting staff, with the exception of Chien-Ming [Wang] early on pulling his hamstring, everybody on the pitching staff has been very healthy. We've been through it."
Strasburg said he has yet to have a conversation with Johnson or general manager Mike Rizzo about the rest of the season.
"No, I'm just focused on the next start. That's all I can really focus on right now. But we're going to have to have a sit-down and talk here soon," Strasburg said.
The only time Strasburg was in trouble Sunday was the fourth. With runners on first and third with two outs, Bryan Anderson hit a fly ball to Bryce Harper in right field. Harper caught the ball and threw out Alan Craig at the plate to end the inning.
"What I was impressed with about that throw was Harper didn't try to airmail it all the way," Johnson said. "When he first got here, that would've been all the way in the air. He actually had a chance to hit the cutoff man there, which was outstanding. But he's got a great arm. Charged the ball well, and he didn't have to look up. He knew he was going home all the way."
The outing for Strasburg was the antithesis of what he went through against the Marlins on Tuesday, when he allowed seven runs (five earned) in five innings. The improvement came after talking with catcher Kurt Suzuki, pitching coach Steve McCatty and bench coach Randy Knorr.
"Yeah, I was just talking to [McCatty] and working with Suzuki and Knorr, and I've been talking to Gio [Gonzalez] a little bit, too, just kind of bouncing ideas of heads," Strasburg said. "I just really wanted to go out there and use all my pitches, not necessarily use one like I did my last outing. It seemed to work a lot better."
By the sixth, the Nationals had a 2-0 lead against right-hander Jake Westbrook. Both runs were driven in by Kurt Suzuki. In the fourth, he homered, then drove in Desmond with a single to center in the sixth.
In his last six games, Suzuki is 8-for-18 (.444) after going 3-for-23 (.130) after joining the Nationals last month.
"Just take the effort out of the swing and just kind of be nice and easy, free and easy," Suzuki said. "The less tension you have, you're going to definitely be a lot quicker. So that's kind of the route we're going right now."
Reliever Sean Burnett entered in the seventh and relinquished the lead, allowing a two-run homer to St. Louis' Daniel Descalso, a .219 hitter entering Sunday.
"He made a bad pitch today," Johnson said. "He got behind, his control has not been as sharp and this is a pretty tough ball club. They've got some left-handers who hit left-handed pitching, and you just can't make mistakes. I thought he was better today except for that one pitch."
But the Nationals won the game.