THE Old Firm derby will be an acid test for improving Rangers, according to former Scotland and Celtic midfielder John Collins.

The Gers welcome their rivals to Ibrox on Sunday with six points separating the two teams in the Ladbrokes Premiership table.

Graeme Murty’s side go into the game on a six-game winning streak, but Collins believes this weekend’s derby clash will show how far they have come since a 0-0 draw between the two sides in their last meeting on 30 December.

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“Rangers haven’t been anywhere near it in the last few years, but they have made progress,” he told Sky Sports.

“The loan signings that they made in the January window have hit the ground running, they’ve made them better.

“They are playing good football, you have got to give the manager credit there, but the acid test is always the big Old Firm game – can Rangers produce it and get a result at home?

“The last three times Celtic have been to Ibrox it has been convincing victories, but that was a Celtic team that was in full flow, attacking, with players in fine form.

“But that’s not the case, Celtic aren’t at the best at the moment, the confidence is a little bit low.

“The manager has had to constantly change his team, so that balances it out. I still think Celtic are favourites for the match though.”

A win for Rangers would cut the gap to Celtic to just three points, albeit with the Hoops still having a game in hand.

But Collins believes there is more pressure on the Light Blues to deliver the three points as they look to end a seven-match winless run against their rivals in the league.

“Celtic are six points clear with a game in hand,” he said.

“Everybody’s saying Graeme Murty needs to win to keep the job on a permanent basis, but I think that would be very unfair on him. I think he has done a very good job, he has made the team better, but there is pressure.

“Rangers haven’t beaten Celtic in a very long time, they’re sitting second in the league behind them although they have made progress, so I think there’s more pressure on Rangers than there is at Celtic, where they are sitting top with a trophy already in the bag. “