The Ibrox hero, who has long admired O'Neill despite their rivalry, admits his biggest concern is the toll management can take on the 74-year-old's health. While McCoist hopes close friend Derek McInnes can guide Rangers to title glory this season, he stressed he would take no pleasure in seeing O'Neill pushed out of Parkhead or forced to continue beyond the point where the job remains enjoyable.

The former Rangers striker believes O'Neill's decades of service to the game, and his achievements at Celtic, mean he deserves the respect to decide for himself when the time is right to step aside.

Speaking to talkSPORT Bet Online Casino, the 64-year-old said: "I think Martin has absolutely earned the right and deserves the respect to stay for as long as he feels right. I really do.

"I would hate Martin to overstay his time at Celtic, first and foremost for his health.

"That's the most important thing, because I've always gotten on really well with Martin. Obviously I want Rangers to win the league 100 per cent, but Martin has more than earned the right to see things out for as long as he wants at Celtic, and that should be the case."

McCoist also concedes Europe's demands could yet play a significant role in the title race.

"I don't think for a minute Martin will say they're prioritising, but their level of performance in Europe has been extremely disappointing. I know they created one or two chances against Benfica, but Benfica were three-nil up and done.

"The performances in Europe have been really disappointing from Martin's point of view.

"I don't have any doubt that it could work in Rangers' favour not having those Thursday European games. Celtic are not allowed, same as Rangers, to get into any game other than expecting to win, particularly at home, whether domestic or European, the fans won't allow it.

"So there is added pressure on Celtic, of course there is. But Martin will be delighted with their league form. I noticed a lovely quote from him this morning where he said it was a fantastic result at the weekend, but if they get beaten on Thursday there'll be another crisis!

"And that's exactly the way it is."