A trio of Celtic's key players are returning to fitness at exactly the right time for Brendan Rodgers' side. 

That's the viewpoint of former Rangers captain Barry Ferguson.

The pundit appeared on Go Radio's Football Show tonight as attentions swiftly turned towards this Sunday's derby encounter between the arch-Glasgow rivals.

Reo Hatate and Cameron Carter-Vickers started as the Hoops ran out comfortable 3-0 winners against Livingston in West Lothian yesterday. 

Callum McGregor remained on the sidelines with a calf strain, however, it is hoped, from a Celtic perspective, that the club captain will be fit in time to play at Ibrox this weekend.

The stakes could not be higher, with Celtic holding the chance to go four points clear at the summit of the table with a victory. 

On the flip side, Rangers could leapfrog them by two points at the top while also having a game in hand to play against Dundee a matter of days later. 

Ferguson is under no illusions of how crucial a game it is for his former side - and he's pinpointed the main dangermen for Philippe Clement's team to watch.

He said: "They are the three most important players at Celtic, there's no doubt about it. You watched the difference they (Carter-Vickers and Hatate) made on Sunday.

"Listen, it takes you a bit of time, when you've been out, to get up to speed but they are so important Carter-Vickers, Hatate and McGregor. I'm sure he'll start on Sunday and that is the spine of your team."

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Fellow pundit Stephen McGinn reckons Rodgers may throw in a surprise or two with his Celtic formation on the day. 

The League One-winning Falkirk player reckons McGregor could be joined by Tomoki Iwata in midfield, with Reo Hatate and Matt O'Riley playing in higher, more advanced positions.

Ferguson responded: "It could be the case. Rangers are playing well but they are pretty physical. I think they will go that way against Celtic.

"I think Dujon Sterling will start on the right-hand side Silva on the left and the three in the middle being Diomande, Lundstram and Cantwell."