TIM Collier is an early doubt for Worcester Warriors' clash at Kingsholm.

The Sixways lock is recovering from a pectoral muscle tear but is facing a race against time to be fit for next Saturday's Premiership derby with Gloucester.

Collier has been one of the stand out performers this season for the Warriors since his surprise move from London Welsh and John Brain, Worcester's director of rugby, today admitted that the 27-year-old could miss his first top flight game of the season.

"He's certainly a doubt at present," said Brain. "It's a muscle tear so it's a question of letting it heal. He's still not training at the moment and he's having treatment twice a day.

"He's not got a great deal of power at the moment because of the injury but it's something that you cannot really put a timescale on. I think, at the moment, he's doubtful for Gloucester but we'd expect him to be fit for our game with Leeds Tykes after that."

Next Saturday's Premiership clash will be their first league outing since the New Year's Day win over London Irish and the break has proved useful for the Sixways walking wounded.

Centres Thomas Lombard and Dale Rasmussen both played through the pain in that clash but Brain is confident that both will be fit for Kingsholm.

"Thomas Lombard's shoulder has improved quite a lot," added Brain. "He'll be fine for Gloucester, while Dale Rasmussen is improving and I'm hopeful he'll be 100 per cent fit in the next 10 days."

Veteran prop Tony Windo is back in training following a minor operation to remove a piece of glass from his hand, while hooker Andre Van Niekerk is fully fit following ankle and hip problems.

Fellow front-rower Chris Hall is now free from concussion symptoms and will take a computer test this week to clear him for involvement next week.