Rangers midfielder Ryan Jack will miss tomorrow's Ibrox clash with Ross County after a flare-up of a calf injury following Sunday's loss to Hearts.

The Gers star picked up the knock at Tynecastle and has been ruled out for up to two weeks - which means he is also likely to miss Saturday's visit of Aberdeen. 

Assistant manager Gary McAllister confirmed the news earlier this morning as he looked ahead to the County match in Glasgow tomorrow evening.

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He said: "Ryan has had a little reoccurrence of an injury in his calf. We're talking 10 days to two weeks."

McAllister also addressed captain James Tavernier's fitness and explained that fellow players Brandon Barker and Jordan Jones need to improve to get an opportunity in the first-team. "[Tavernier] is a couple of weeks away," he added. "He's back on grass and is a fit guy so we hope to potentially have him back sooner.

"Recently Barker and Jones have both been injured so they need to now show more to get back into the team. If they show enough in training they'll get an opportunity."

It comes in the wake of reports that Steven Gerrard had deemed the latter duo surplus to requirements and was willing to allow them to leave this month.