On Saturday October 17, Aguero was caught on camera placing his hand on assistant referee Massey-Ellis’ shoulder during the first half of the game at the Etihad.

Touching a match official is usually punished by a yellow card, unless the physical approach is deemed aggressive in which case the player will be shown a red card. But Aguero's actions went unpunished and he will not face any retrospective action over the incident.

As well as simply breaching the laws of the game by touching a match official, Aguero was also accused on Twitter of controlling her and exhibiting sexist behaviour due to the lineswoman’s gender.

Pep Guardiola later defended his player as ‘the nicest person he's ever met in his life’.

The manager said of Aguero: “Come on guys. Sergio is the nicest person I ever met in my life. Look for problems in other situations, not in this one.”

However, former Premier League referee Mark Halsey said he thought Massey-Ellis handled the situation very well.

“Only Sian and Aguero know what went on in,” he told talkSPORT.

“Sian felt there was no further action required, so maybe she thought ‘okay, there’s no problem, it’s part of the game’.

“If there was anything untoward or insulting language used or she felt something wasn’t right, then Sian would have called the referee over.”

Asked if she felt under pressure not to call the referee over given her gender, Halsey reiterated his belief that Messey-Ellis would not have been intimidated saying if she felt intimidated by Aguero then she would have brought it to the referee’s attention.

“I’ve worked with Sian on a few occasions and she’s an excellent assistant referee. There’s no doubt that if she had felt intimidated then she would have called the referee over and had Aguero either cautioned or dismissed from the field of play.” Halsey said

Rangers led 3-1 with 13 minutes to play as Diogo Goncalves found his own net and goals from Glen Kamara and Morelos followed Nicolas Otamendi's red card - all on the back of Connor Goldson's own goal in the first minute.

However, Rafa Silva pounced on a Filip Helander error before substitute Darwin Nunez levelled at the death in an enthralling contest.

Steven Gerrard's men remain unbeaten and in second place in Europa League Group D with Lech Poznan sinking Standard Liege 3-1 in the other pool fixture.

But this draw will feel like a loss having dominated so much of the contest against the group leaders, who have now gone 25 Europa League matches without defeat at home.

Reaction & as it happened

It speaks volumes about Rangers' overwhelming supremacy that so many of the players in away colours will be devastated at taking merely a point in the back yard of such a formidable opponent.

That, though, is not how things began. In the early skirmishes, Gerrard's men flailed. The Benfica opener, after barely 60 seconds, was a grievous act of self-harm and hinted at a long and painful night.

Helander, who had a desperate evening, ballooned a clearance to Silva. The forward bamboozled him en route to the by-line before his cut-back cannoned in off Goldson.

At this point, Benfica were swarming Rangers' half. The ball fizzed neatly between the red jerseys, and Pizzi ought to have made it 2-0 but dragged across the face from inside the box.

The game turned in a heartbeat on 19 minutes thanks to one flash of attacking incision and one act of defensive misjudgement.

Steven Davis floated a swinging pass in behind a high Benfica line for Ryan Kent, and the forward was clipped and sent sprawling by Otamendi. It was a blatant red card and it jolted Rangers into life.

Imbued with new belief, Rangers roared forward. Davis, on the right this time, sent James Tavernier clear up the flank, and the captain's square ball was viciously - and comically - lashed into his own net by Goncalves.

The ball whizzed home like a wild slice off a golf tee.

Darwin Nunez celebrates scoring

Darwin Nunez scored Benfica's equaliser in the 91st minute

There was nothing slapstick about Rangers' second, arriving less than a minute a later as they landed a wicked double-blow. Morelos galloped down the same right touchline and his drifted cross-field pass hit the feet of Kamara.

The Finn chopped on to his right foot and caressed a brilliantly placed low shot beyond Odysseas Vlachomidis.

In the second half, predictably and poignantly, Morelos had an emphatic say on his 37th European outing. The Colombia striker scooped in Tavernier's piercing square ball to break the 21-goal record set by Ally McCoist.

Kent clipped a post after being cannily teed up by Ryan Jack, then swerved wide from a similar position, while the goalkeeper smothered at the feet of Tavernier and blocked Morelos from point-blank range.

Even then, there was no indication of an impending fightback, no sign of a pulse in the flat-lining home side.

Silva soon applied a defibrillator though, aided by another Helander error, when he forcing past Allan McGregor.

Then, in the 91st minute, Nunez got between the visiting centre-backs and planted a shot into the Rangers net and a dagger into Rangers' hearts.

It was a sore blow, denying Gerrard's men a third win from three in the group, top spot in the table, and an almighty away victory.

Man of the match - Steven Davis

Steven Davis

Morelos was excellent, Tavernier supreme down the right, but Davis’ imperious midfield quality was crucial to almost everything good about Rangers. His range of passing, composure and bite were outstanding.

What did we learn?

Rangers have the attacking panache and breadth of options to wound high-calibre teams, and did not capitulate after the shock of Goldson's own goal.

They bossed the hour that followed, but were undone twice defensively in the dying minutes. Even against a depleted opponent, it was a painful lesson in concentration and accuracy.

Match statistics

Benfica remain unbeaten in all 24 of their Europa League home games since the competition was rebranded in 2009, winning 19 and drawing five.

Rangers conceded three goals in a match for the first time in 20 games in all competitions (1-3 v Bayer Leverkusen in March). Indeed, they shipped more goals tonight than they had in their previous nine games in all competitions combined (two).

There were just 88 seconds between Diogo Gonçalves' own goal equaliser for Rangers, and Glen Kamara giving the Scottish side the lead.

This was the fourth different Europa League game in which both sides netted an own goal, with half of these now involving Rangers (v Benfica and also v Spartak Moscow in November 2018).

Connor Goldson's own goal to give Benfica the lead was the fastest own goal scored in the Europa League (60 seconds).