CELTIC have been rocked by another injury blow on the eve of tomorrow's Old Firm showdown at Ibrox.

Already without skipper Stephen McManus following surgery yesterday on the captain's damaged knee, Lee Naylor is now a big doubt for the match after suffering an injury at Aberdeen last weekend.

He was sent for tests earlier this week to determine the extent of the problem, believed to be a stomach muscle injury. But the left-back has not been able to train in the run-up to the game against Rangers.

Gordon Strachan has a major dilemma if he fails to make it because replacements Darren O'Dea and Mark Wilson have also been out. O'Dea had believed he had recovered from the hamstring and ankle injuries which have sidelined him in recent weeks, but was forced to call off during the warm-up at Pittodrie last weekend after being listed among the subs.

Strachan has had to delay O'Dea's return to training until today to give him the best possible chance of avoiding another setback.

Wilson also had to be ruled out of the squad for the game at Aberdeen after picking up yet another injury.

Strachan has reserve team captain Ryan Conroy is on standby alongside Barry Robson.

But, while the Scotland international has suffered no reaction since making his return to full training yesterday following his adductor muscle surgery, he has not played a game at any level since February 1. But the mobility and goal threat of Georgios Samaras is available again to Strachan after the Greek striker successfully returned to training last weekend.

With Scott Brown serving the final game of his two-match ban, the manager is considering all his options, and they include a possible return in midfield for either Shaun Maloney or Willo Flood.

Flood has not figured since he started against Hearts at Tynecastle a month ago.

But his running power could be very useful either from the start or, more likely, injected later in the game.