Brendan Rodgers has explained why Callum McGregor is not ready to start games for Celtic as he continues his recovery from injury. 

The Celtic manager was able to call upon his captain for the final 25 minutes of last weekend's 3-3 Glasgow derby classic with Rangers.

But Rodgers has confessed the 30-year-old, who has been struggling with an Achilles problem since a hobbling off at half-time against Dundee six weeks ago, shouldn't be pushed back into action too quickly and wants to manage his minutes. 

Asked about McGregor's inclusion on the bench for today's Scottish Premiership clash with St Mirren, the Hoops boss said: "He understands, Callum and I go back a long time so our communication is always open and very honest. So, he knows where he's at. 

"He's been out for a long time and he done absolutely fantastic to have some sort of availability for the Rangers game. But you cannot, after five weeks of virtually doing nothing, and then back in a couple days and being involved in Rangers, expect to be at that level of fitness from when you last were there. 

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"I think it was February 28 or something, his last game (start) against Dundee, so he's not at that level yet. But he's certainly got an impact to play for us, because on and off the pitch he's absolutely vital for us."

Injuries to key players have seen Rodgers have to shuffle the pack in recent times, Mark Nawrocki comes into the Celtic backline to partner Cameron Carter-Vickers today, with Liam Scales sidelined. Gustaf Lagerbielke and Stephen Welsh are also on the bench, who are capable of filling in at centre-back. 

Discussing the depth of his squad and the importance of another fast start with Celtic given the opportunity to go four points clear at the league summit should they win today, Rodgers stated: "I think there's not so many games now, so you can't waste time in not performing.

"Our idea is to, like we did last week, start the game very strong with a big energy, bring the crowd with us, and the pitch is in really good shape, there's a nice little zip on it. So, we want to get the tempo of the game high and really test the organisation out of St Mirren.

"If we can do that then hopefully we can have a good day."