Rangers have been rocked ahead of the first Old Firm derby of the season after Covid struck within the Ibrox camp.

Manager Steven Gerrard and a number of first team players missed this week's Europa League play-off clash against Alashkert, but the Light Blues managed to book their spot in the group stages.

Here's what we know so far ahead of Sunday's crunch match against Celtic at Ibrox.

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How many cases are there at Rangers?

The Scottish Premiership champions confirmed positive tests have been identified meaning it is more than one case of the virus.

But there is no indication on whether the cases are limited to a small number of people or a wider outbreak.

READ MORE: Rangers receive Old Firm squad boost after Europa League Covid scare

Who has tested positive for the virus at Rangers? 

Currently the Ibrox club have chosen not to reveal who has tested positive for Covid.

It's not clear which players or members of staff have returned positive tests.

Who didn't travel for the Alashkert match in Armenia?

There is still no clarity over whether any players or staff have tested positive but a number of first-team players did not travel to Armenia.

Manager Steven Gerrard was a notable omission from those who flew from Glasgow with six first-team players also not on board.

James Tavernier was absent as well as Calvin Bassey, Scott Wright and Ryan Kent. Goalkeepers Allan McGregor and Jon McLaughlin didn't travel with the squad either.

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Who could return for the Celtic match?

Rangers assistant manager Gary McAllister said after Thursday's Alashkert clash: "Scott Arfield took a sore one on his toe but all fine after the match.

"We also have players returning from suspension so we have more bodies in the squad for Sunday."

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It is understood that Ryan Kent could return after missing the trip to Armenia due to a hamstring inury.

Suspended duo Kemar Roofe and John Lundstram could also return.

Rangers could also welcome back more of their stars who are self-isolating - if they are double vaccinated and can return negative PCR tests.