DARLINGTON striker Alun Armstrong is struggling to be fit in time to face Cambridge United tomorrow.

The 30-year-old was due to resume full training with Quakers yesterday, before setting off for Cambridgeshire with the rest of the squad this afternoon.

However, assistant manager Mark Proctor has conceded the 11-goal forward remains short of fitness after failing to recover from a calf injury.

Armstrong has missed Quakers' last two games and has been undergoing a rehabilitation programme in Ipswich, where his based.

"Alun is a big doubt and as it stands he won't be fit to play at Cambridge," said Proctor. "We will make a further assessment on Friday, although it doesn't look too promising."

With five games to go, and seventh-placed Quakers occupying the final play-off spot, Proctor insists Armstrong will not be rushed back.

"If we threw Alun straight back in then it could be seen as a gamble," admitted Proctor. "We would rather lose him for just the Cambridge game, rather than risk losing him for the rest of the season."

If Armstrong fails to recover in time, Craig Russell will continue to partner Clyde Wijnhard in attack.

On-loan Middlesbrough defender Matthew Bates is unavailable to make his debut tomorrow.

He joined Quakers on loan until the end of the season on transfer deadline day, but has remained with the Teessiders to recover from a back injury and won't link up with Quakers until Monday.

"It is a setback, but we have to respect Middlesbrough's wishes," said Proctor. "Matt is only young, but he commands his area really well and we could have done with his presence at Cambridge."

With Bates' bow on hold, Matty Appleby is expected to continue defensive duties.

Proctor has also hinted that midfielder Stephen Thomas could make his first start since October. The 25-year-old has suffered numerous fitness setbacks since joining from Wrexham during the summer.

"With Matty at the back we haven't really had anyone to provide that holding role in midfield," said Proctor. "Stephen is the kind of player who can provide that stability and is certainly an option."

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