Steven Gerrard's side stay six points behind leaders Celtic after a Morelos brace, James Tavernier's penalty and a Jermain Defoe strike earned the points.

Morelos and Scott McKenna, who were involved in an incident in the first game of the season, were both shown red cards after appearing to aim kicks at each other in a challenge.

At that stage, the scoreline was 3-2 after Sam Cosgrove scored his second of the game from the penalty spot but, as Aberdeen searched for a leveller, Defoe secured Rangers' win.

The victory moves the Ibrox side five points ahead of Aberdeen, who remain third.

Morelos & Kent torment Aberdeen

The three previous meetings between these foes this season had been dominated by Rangers, but Aberdeen emerged victorious in two of them - both 1-0 - and drew the other. There had been red cards in each of those league meetings too - two of them for Morelos and another for Cosgrove, the Scottish Premiership's top goalscorers.

All the signs suggested this was going to be a tight, thunderous affair - and so it proved.

Ryan Kent has been in superb form for Rangers and had a hand in both of Morelos' goals. First, the on-loan Liverpool forward slalomed his way past Shay Logan and into the Aberdeen box before unleashing a venomous shot which Joe Lewis could only parry into the path of Morelos, who rolled it into the net.

Not to be outdone, Cosgrove showed he too is adept at the art of poaching, tapping home after the ball ricocheted off Tavernier and Connor Goldson following Lewis Ferguson's fizzing volley.

Rangers had only lost one of the 16 games in which they had led this season, but just seven minutes after Aberdeen equalised they were back in front. Kent drove at the defence and slid a pass to Morelos who, on his left foot, shaped a sublime finish past McKenna and Lewis and low into the net for his 23rd goal this term.

The Pittodrie crowd had barely settled again before Rangers were awarded their fifth penalty in two games. McKenna thrust up a hand to claim for something and Tavernier's free-kick struck it, clear as day. The Rangers captain stepped up and dispatched the spot-kick, his third successful conversion of the week, and Rangers had daylight.

Rangers emerge from the chaos

The madness only paused fleetingly before ensuing again as, a minute after the restart, the hosts were given a lifeline. Tavernier hauled down Ferguson and Cosgrove fired the penalty straight down the middle and past Allan McGregor.

It was truly breathless stuff, punishing to even watch. Morelos had a glorious chance for his hat trick, but when clean through he hit straight at Lewis. He had been unplayable all night. But then came the other side of the Colombian, the ill-disciplined, tempestuous side.

A ball was lumped forward and in typically boisterous fashion, Morelos hared after it to make sure McKenna had no easy way out. But as the two tussled for the ball, the Aberdeen defender fell and Morelos lashed out at him - as he had done in the opening match of the season at Pittodrie. But McKenna was no innocent as he too looked to jab a foot at the Rangers striker as he tumbled to the ground.

Referee Bobby Madden took his time, gathered his thoughts and decided both deserved to be dismissed.

There were further flashpoints as McGregor smothered a through ball and planted his studs on the onrushing Ferguson, before the Aberdeen midfielder returned the favour shortly after.

Amid the chaos, Rangers still held a slender advantage and Aberdeen pressed for the equaliser. Substitute James Wilson, Stewart and Gary Mackay-Steven all came close, McGregor instinctively pushing Stewart's shot clear as it flew through a ruck of bodies.

But try as they might, the necessary quality evaded the hosts, and eventually Defoe slammed home after a swift break to ensure Rangers clinched the points in an enthralling encounter.

Allan McGregor's instinctive save denied Greg Stewart an equaliser

'Plenty talking points' - analysis

BBC Scotland's Tyrone Smith at Pittodrie

It was quite a night in the Granite City in a fixture that delivered plenty of talking points.

One of them is the fact Rangers have secured a crucial win at the home of one of their main Premiership rivals, delivering a real statement about their own title credentials.

The other is the writing of the latest chapter in the enduring Scott McKenna v Alfredo Morelos saga. Their double red card will undoubtedly be the source of plenty of headlines.

In among all of that, there were some top-drawer goals too.

'This gives us breathing space' - reaction

Aberdeen manager Derek McInnes: "Morelos was fantastic in leading the line for them. It was a pretty even game but he made the difference. When he got sent off, we were the better team.

"It's a sore one but there's 13 games to go and we'll dust ourselves down. I feel that we will get better but there's no real room for error."

Rangers manager Steven Gerrard: "Obviously, I'm delighted with the win. I thought we stood up to them and matched them on the basics very well. We took our goals ever so well.

"This gives us a little breathing space but we know Derek McInnes will keep pushing until the end. Aberdeen have been in great form. We know they're not going to go away."