Manchester City couldn't have produced a more emphatic performance in their opening fixture of the Champions League stage on Wednesday.

Pep Guardiola watched on in delight as his men strolled to a 4-0 victory over Feyenoord at De Kuip thanks to a John Stones brace and goals from Sergio Aguero and Gabriel Jesus.

The result is the Citizens’ biggest-ever away win in the Champions League and their first on the road in seven previous attempts.

City fans are right to be full of optimism this season having watched Guardiola assemble a squad with the quality and depth to handle the demands of four separate competitions.

At least that’s the impression they give on paper – and one would like to think they would after spending an eye-watering £220 million on new signings this summer.

Guardiola is subsequently under significant pressure to deliver at least one major after coming up empty-handed at the end of his first term at the Etihad.

The luxurious squad at his disposal is one that simply must achieve success, and they took the first step towards fulfilling their European ambitions with a resounding win in Holland.

But despite the one-sided scoreline, not every last detail went according to plan for City.

MENDY'S EMBARRASSING MOMENT

Benjamin Mendy – the most expensive arrival in the blue half of Manchester this summer – suffered one rather embarrassing moment during the otherwise comfortable outing.

The £51 million left-back was humiliated by Feyenoord’s Steven Berghuis when the winger poked the ball through his legs to pull off what has to be one of the simplest nutmegs of his career.

Luckily for Mendy, it occurred near the halfway where City could recover and deal with the danger – but his teammates are unlikely to let him live it down anytime soon.

Kyle Walker was quick to remind the France international of the regrettable moment, sending him a humorous tweet soon after the match.

KYLE WALKER'S TWEET

Accompanied by a video of the nutmeg, the 27-year-old wrote: “Close them legs my friend.”

Watch Mendy be left red-faced in the video below.

MENDY'S RESPONSE

Oh dear, Benjamin.

It can happen to anyone, but the video certainly isn't one Mendy will be happy to see doing the rounds on social media. 

So much so, that he jokingly claims to have no knowledge of the nutmeg everyone is discussing.

"Sorry I dont know what nutmeg you are talking about guys," the Frenchman tweeted.

Even the City social media staff refused to sweep it under the carpet.

But Mendy didn't leave it there – he attempted to get back at Walker with a cheeky tweet of his own.

Safe to say, it doesn't quite stack up to Walker's initial dig.

See for yourself below.

Rather than looking for a brilliant comeback, perhaps Mendy would be better of simply following Walker's advice next time he's marking a tricky winger near the touchline.