The LA Galaxy has confirmed on Thursday that captain Robbie Keane has underwent successful surgery on his right knee and is expected to miss 4-6 weeks.
Keane had missed both of the Republic of Ireland's friendlies during the international break and had been flown back to Los Angeles after revealing pain in his right knee.
Keane is the latest name to be added to Bruce Arena's injury list, with Giovani Dos Santos and Dan Kennedy recently resuming training following injuries in the Galaxy's MLS opener.
Meanwhile, Steven Gerrard, who was subbed off three minutes into the Galaxy's 3-1 win over the San Jose Earthquakes, has not trained with the team in two weeks.