Nationals shortstop Ian Desmond will miss at least a month with a torn oblique. (US Presswire)

The Nationals extended their lead in the National League East to 3 1/2 games with a victory over the second-place Braves on Sunday, but lost All-Star shortstop Ian Desmond to the disabled list with an oblique tear. He'll miss at least a month.

Desmond left Saturday's game in the eighth inning because of tightness in his left oblique. He also missed the All-Star Game because of the injury. An MRI showed a tear, manager Davey Johnson said in his postgame new conference.

Johnson said Danny Espinosa will move from second base to shortstop, and Steve Lombardozzi will play second. The team may call up outfielder Corey Brown, who is hitting .300/.384/.559 with 21 home runs at Triple-A Syracuse, Johnson said. The lefthanded hitting Brown was pulled from his game on Sunday, signaling that he would be called up.

The team also has Mark DeRosa, who can play middle infield. DeRosa missed six weeks this season with an oblique injury. He has not played shortstop since 2008.

Desmond is hitting .286/.322/.503 with 17 home runs for the Nationals this season, earning a deserved first All-Star nod.

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