Chris Rusin made an impressive major league debut for the Chicago Cubs on Aug. 21 when he allowed just one run over five innings in a loss at Milwaukee.

On Tuesday night, he looked more like a rookie.

Rusin was pulled in the second inning after allowing five runs on eight hits as Chicago lost 11-5 to the NL East-leading Washington Nationals.

Adam LaRoche hit two of Washington's six homers and Ian Desmond had four RBIs for the Nationals, who opened a season-high 7½-game advantage in the division. Second-place Atlanta lost to Colorado 6-0 on Tuesday night.

The Cubs have lost four straight.

Rusin (0-2), who was recalled from Double-A Tennessee before the game, was pulled after the first four batters reached in the second. It was the Cubs' shortest start of the season.

"Without breaking balls you better keep it down and you better have movement and today he didn't have either. The cutter wasn't doing a whole lot and you couldn't get the ball to sink or keep the ball down," said Cubs manager Dale Sveum. "He threw a few good changeups, that was about it. It's tough to get through a major league lineup, lets alone that lineup, with a flat fastball."

Desmond hit a two-run drive off Rusin (0-2) in the first for his 20th homer. The All-Star shortstop added a two-run double after Jesus Flores homered in Washington's three-run second.

"I just didn't keep it down and when I missed my spots they capitalized and did what they were supposed to do so, I give them credit," Rusin said. "This is the big leagues and you can't miss your spots here because that will happen."

Despite Tuesday's outing, Rusin has a chance to make an impression on Cub management over the next month.

"That's what you want to do, but you can't have outings like this. You've got to go out there and keep the ball down, hit your spots and hopefully make an impression," he said. "But I didn't do well tonight. Hopefully I'll learn from my mistakes and bounce back next time."

Chicago used seven pitchers, five in the first five innings as Washington built an 8-1 lead.

LaRoche and Jayson Werth had four hits apiece for the Nationals. Desmond, Jesus Flores, Tyler Moore and Ryan Zimmerman also went deep. The six home runs matched a team record.

Every Nationals starter had at least one hit.

Alfonso Soriano hit his 26th homer and a two-run triple for the Cubs and Starlin Castro drove in two runs.

Washington right-hander Edwin Jackson (9-9) allowed four runs and seven hits in 5 2-3 innings.

"He's very tough, he's got a good fastball and a good slider," Soriano said of Jackson. "Every year that I face him he's getting better."

Chicago has eight losing streaks of at least four games this season.

"We have to try to come back one day at a time. We lost yesterday, we lost today. We have to come back with more energy and try to get the win tomorrow," Soriano said.

NOTES: The Nationals also hit six home runs on May 20, 2011, in Baltimore. ... RHP Jaye Chapman, who also was recalled from Double-A Tennessee on Tuesday, Socolovich and C Anthony Recker made their Cubs debuts. Chicago has used 29 pitchers and 52 players, both franchise records. ... NASCAR driver Kurt Busch threw out a ceremonial first pitch. ... Washington LHP Gio Gonzalez (17-7, 3.10 ERA) will face RHP Chris Volstad (2-9, 6.06 ERA) when the series resumes on Wednesday.