Former Celtic full-back Mark Wilson thinks that Rangers will need to strengthen their squad in the transfer window if they are to have any chance of challenging for the title, because there is no way Brendan Rodgers will allow the champions to rest on their laurels.

Celtic have gone into the winter break enjoying an eight-point lead over their closest challengers, though the Ibrox side do have two games in hand.

But Wilson believes that there is no way Rangers can overturn that deficit if they don’t add to their squad during January, because not only will Celtic be even stronger after the break due to players returning from injury, but their manager Rodgers is also certain to add quality in key areas of his team.

"I think Rangers will strengthen and they need to if they're serious about challenging Celtic,” Wilson said.

"When the manager [Rodgers] comes out and says he wants four players [earlier in the season], I think it would look strange if he didn't get at least a couple in.

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"I think [Celtic] will strengthen. I think they've got to strengthen not only for this season, but if they're going to go into the Champions League next season with a more settled squad and actually have a go at it, then you need to integrate players into the squad more quickly. Rather than just giving them a few weeks.

"I think they'll add a few. I'd like to see them add a striker to lighten the load on Kyogo (Furuhashi). I'm not too sure Oh (Hyeon-gyu) is the answer. He's had a year here and is still young. But I think they need someone to really push Kyogo.

"And a goalkeeper as well. Joe Hart, I still think has got legs in him, but I don't think he's got anyone really pushing him either.

"So, it's both ends of the pitch for me."

Despite his certainty that Celtic will add players from a position of strength this month, Wilson sees the return of Liel Abada and Reo Hatate – once he comes back from the Asian Cup – as being potentially pivotal for Celtic’s chances of success in the second half of the season.

With four impressive wins in a row under their belt to round off the first half of the campaign, he thinks that the mid-December slump that saw Celtic record back-to-back defeats to Kilmarnock and Hearts will soon be a distant memory, and that Rodgers is finally winning over even his harshest critics.

"I think they're in a lot better place than they were four or five weeks ago,” he said.

"Before that it was a trickier time for Brendan Rodgers. I always felt there was a wee bit of unrest with the fans just waiting for something to go wrong. When it does go wrong, the pressure then comes on your shoulders pretty quickly.

"I felt he dealt with that well and those four games before Christmas were key. Not only just to win them, but to get performances as well.

"It started slowly against Livi but then much better against Dundee. Obviously, the high point was against Rangers when they were much more like themselves. They topped it off with the win against St Mirren.

"Sometimes teams just go through that wee period. It was lost on a few people, myself included, the key players missing from the side.

"Everyone thinks because Celtic have got this unbelievably large squad that it's not going to affect them. But of course it does.

"The likes of Hatate and Abada were missing, the centre halves were chopping and changing as well. That's going to affect you and it did affect them.

"I think they'll be a lot better coming back from the break with a fit Hatate and a fit Abada."

Abada in particular can make a huge difference for Celtic according to Wilson, who reckons they have struggled to replace the productivity of both the Israeli on the right and Jota on the left of their attack so far this season.

Luis Palma has started to fill the void on one side, and the re-emergence of Abada on the other should, in theory, bolster Celtic’s attacking threat still further.

"Since his debut he has been [vital],” he said.

“He scored on his debut and hasn't stopped from there.

"He's like any winger. Sometimes it can be hit and miss on the ball.

"Everyone's obsessed with stats these days and what wide players can produce. He's right up there in terms of assists and goals, so there's no doubt any team would miss him.

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"That's been a position that's been chopped and changed this season. Yang (Hyun-Jun) was given a go out there, James Forrest [was] brought back in and Mikey Johnston as well.

"None have really stood out. Even when (Daizen) Maeda came back, he looked a bit rusty.

"No doubt a fit Abada just comes straight back into that starting XI."