Robbie Keane

Robbie Keane will miss the Republic of Ireland's friendly with Slovakia on Tuesday due to a knee injury, Irish head coach Martin O'Neill confirmed.

The 35-year-old forward has not trained since joining up with the Irish due to the injury and missed Ireland's friendly with Switzerland last week. Keane has returned to Southern California to get his knee examined by the Galaxy's medical staff. 

According to O'Neill, Keane suffered the injury during the LA Galaxy's 3-1 victory over the San Jose Earthquakes two weeks ago, but neither the Irish training staff nor the Galaxy captain are certain when the knock occurred. 

"He was concerned about it because he doesn't remember exactly what happened," O'Neill told reporters in Ireland's pre-match press conference. "It might have been a little bit of a knock and, of course, when that's not going away immediately, then you start getting a bit of a concern. He feels as if he might just get it scoped and have a little look around to see what it is. In this day and age, that doesn't take too long. 

"I don't think he has got any real worries, but obviously, we will know when he goes back [to LA]."