Central Coast Mariners striker Matt Simon is in doubt for tomorrow night's clash with North Queensland Fury in Townsville.

Simon is battling a back injury but will be given every chance to prove his fitness as the Mariners strive to close the gap on the top three against the bottom-placed Fury.

Also under an injury cloud is central defender Chris Doig who is suffering from a quadricep strain and Mariners boss Lawrie McKinna said the Scottish centre-half could miss a few more matches than initially suspected.

"He'll keep working on it but at this stage he might miss a few games which is disappointing," McKinna said.

McKinna said that the Mariners were hoping for a positive away result before facing the Perth Glory at home next weekend.

"After so many away games we want to get a good result in Townsville and come home with confidence," he added.