Steven Gerrard’s side brought Celtic’s nine-year reign over the Scottish Premiership to an end last season, beating the Bhoys to the title by a whopping 25 points.
Celtic will be looking to close the gap and reclaim their place as Scottish champions this season, but their fans will be concerned about how far they have fallen behind the Gers, feels McCann.
The former Rangers forward insisted that the Light Blues have a significant lead over their arch-rivals due to the quality and depth they have in their squad.
McCann, who expects Celtic to be Rangers’ top rivals this season, stressed the need for the Hoops to hit the ground running under Ange Postecoglou and make significant additions to their team as they cannot afford to let the Gers have a lead in the title race like last term.
“I think Rangers have opened up a gap which will, if you are a Celtic fan, will concern them, how big that gap has opened up and how quickly it has opened up“, McCann said on Rangers TV.
“I expect Celtic to make a couple of really good signings, they will have to.
“They will have to get the support energised to say that ‘We are in the race here, we’re just not going to concede that we’ve fallen behind Rangers, it is going take two seasons to get back’.
“I think there is probably a belief that they are going to have to work really hard under Ange.
“And there they are going to have to really hit the ground running in the season because what they don’t want to do is to give this side a lead because then they are not going to catch them.
“They are not going to catch Rangers because Rangers have proven that they are really good frontrunners as they did last season.
“But, I do believe the challenge will come from Celtic, expect Hibs to be strong again this year, it will be interesting to see how Aberdeen do.
“I think the main contender will be Celtic again, but, at this moment in time, I do believe they are quite a bit off of Rangers due to that depth of quality.“
Rangers got their Scottish Premiership campaign off to a winning start, beating Livingston 3-0 on Saturday, while Celtic suffered a 2-1 defeat at the hands of Hearts.