Celtic found themselves a man down after Callum McGregor collected two quick-fire bookings but were level briefly through Odsonne Edouard.

But there was another dose of indignity for Brown and co as Rangers powered on to their biggest derby victory since 2007.

Not only have Gerrard's team blown apart their rivals' 10-in-a-row dreams, but they have now also completed an unbeaten top-flight season against Celtic for the first time in 21 years.

And they now only have Livingston and Aberdeen to overcome as they seek to round off an invincible league campaign.

Brown was bowing out after 44 derbies but it was Jack Simpson's first for Gers as the former Bournemouth ace stepped in to replace Filip Helander.

It was also referee Nick Walsh's first taste of action between Glasgow's big two and it was his determination to stamp his authority early which sealed McGregor's fate.

The clash started in ragged fashion but soon became an engrossing, back-and-forth affair.

It was obvious Walsh was eager to get his cards out early. Simpson was certainly harshly done by as he was booked after a coming together with Edouard, while McGregor will have similar thoughts on the yellow he collected on the 23rd minute for a innocuous trip on Ryan Kent.

Having backed himself into that corner, Walsh had no choice but to reach for his red when the Hoops midfielder then caught Glen Kamara late three minutes later.

But, in fairness to the referee, his use of the advantage rule was spot on as Gers worked the ball to Joe Aribo out on the left. Ryan Kent let fly from a cut-back but it was Roofe's cute use of his chest to steer the ball into the bottom corner that brought the opener.

As the hosts celebrated, Celtic were hit with a second blow as Welsh returned to McGregor to direct him down the tunnel.

But it had hardly been all Rangers until this point. Allan McGregor pulled off his latest vital derby intervention this term to tip a Mohamed Elyounoussi strike onto the bar just before the opening goal.

However, the Ibrox keeper was badly let down by his defence as Simpson and Borna Barisic failed to keep hold of their men as David Turbull swung over a corner on the half-hour mark, with Kristoffer Ajer's knockdown headed home by Edouard from point-blank range.

Scott Bain was busy as well making saves from Roofe and Aribo – but a drama-filled seven-minute period took another turn as Rangers regained the lead again.

Celtic were pinned down as the failed to escape from a Gers corner. Morelos picked the ball up to the right of the box, stuck the ball between Brown's legs in the ultimate act of disrespect before flashing another stunning hit past Bain.

Again Celtic had chances, though, with James Forrest and Turnbull wasting golden chances either side of the interval.

But with the man advantage, Rangers were finding it easier and easier to create space.

And they made it count on 57 minutes. Roofe sprayed the ball out to Barisic and hared into the box to get on the end of the Croat's cross as he powered his header past Bain.

That was Brown's final involvement as John Kennedy spared the captain any further humiliation, introducing Ismaila Soro.

But the anguish for Celtic was not over yet as as Defoe squeezed the fourth past Bain in injury time.