Wanderers' highly-rated full-back Joey O'Brien could be ruled out for the whole season.

The Republic of Ireland international is undergoing a rehabilitation programme following knee surgery and is not expected to resume training for another three to four months.

O'Brien, aged 20, has not featured for Bolton in the current campaign after suffering the setback in pre-season.

Manager Sam Allardyce initially thought the defender would be available for part of the festive programme but those hopes have been dashed.

The Wanderers boss said: "Joey is really distraught. When he finished here last year he was on a high after playing 28-30 games.

"Then before the season got under way, he was stricken by an injury.

"He has experienced the accolades, now he is experiencing the cruelty of the game.

"Joey is on a rehabilitation programme and is going to be out for another three to four months.

"As he has had surgery we have to make sure we get this injury 100 per cent right for his long-term future."