Outfielder Corey Brown, a September call-up, is likely out for the season’s remaining two weeks following surgery to remove an infection from his knee, Manager Davey Johnson said. Brown had stayed behind in Washington when the Nationals traveled to New York after team doctors grew concerned that Brown might have a staph infection.

“It wasn’t progressing as it should, and the orthopedic surgeon that we have had to open his knee up and get the infection out of there,” Johnson said. “I’m not a doctor, but I know one thing: You don’t mess around with a staph infection.”

The Nationals acquired Brown, 25, in the trade that sent Josh Willingham to Oakland and also brought reliever Henry Rodriguez to the Nationals. Since his call-up last Tuesday, Brown appeared in three games, all as a pinch-hitter, and went 0 for 3 with two strikeouts. At Class AAA Syracuse this year, Brown hit .235/.326/.402 with 14 homers in 462 plate appearances.