Manchester United defender John O'Shea is expected to miss the rest of the season with a blood clot.

The 28-year old has been out of action since receiving a knock on his leg in the second leg of Ireland's much-publicised and ill-fated World Cup play-off against France in November and it has now been revealed that the problem has become worse than first thought.

"John has a terrible injury, one of those which is unusual," Red Devils boss Sir Alex Ferguson said.

"It's like a dead leg, except a dead leg usually last for only three or four days.

"The problem is that the blood clot became all knotted and you get calcification.

"It's a long process and he'll probably miss the season now."