Manchester City effectively sealed their progress to the quarter-finals of the Champions League with a stunning last-16, first-leg demolition of Sporting Lisbon in Portugal.
As they have done for much of this season, City put on a majestic display to give themselves a surely unassailable advantage in a tie against what had been a buoyant and reinvigorated Portuguese champions.
Bernardo Silva was brilliant, silencing the boos that greeted every touch from him and City's three other former Benfica players with his side's second and fourth goals, the first a glorious half-volley following a corner.
In-form Riyad Mahrez was on the scoresheet again with a close-range finish awarded via VAR after a lengthy delay to assess if Kevin de Bruyne had strayed offside in the build-up, as originally ruled.
Phil Foden also added to his growing collection of cool, calm finishes in a relentless first half that shattered Sporting.
There was no let-up after the break, with Silva seeing a hat-trick headed goal ruled out for offside before he set up Raheem Sterling to curl in a lovely fifth.
The result equals the biggest winning margin in an away match in the Champions League knockout phase and gives City their joint biggest European away victory, level with the 5-0 win at Steaua Bucharest in the play-off round of this competition in 2016-17.
Sporting will travel to Manchester for the formality of the second leg on Wednesday, 16 March.
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"I am absolutely more than delighted," said Guardiola. "We know how difficult it is, this competition. We were so clinical - arrive, goal, arrive, goal, arrive, goal. When it is like this it is difficult for the opponent.
"We defended well and got an incredible result but we have a duty as a manager and team to analyse how we performed, not just the result.
"We have to take care of the ball better. One of the rules I have is when you have the ball try to pass to someone in the same T-shirt. Today we lost the ball many times.
"The difference was that we were so clinical. Then it is difficult for the opponents and we have confidence. It is a dream, a perfect result, so good for the second leg but we can do better."
City show their Champions League credentials
Pep Guardiola's City remain a domestic behemoth, with a fourth Premier League title in five years now theirs to lose after taking 43 points from the past 45 available to leave them nine points clear at the top of the table.
In Europe, though, they are ravenous for a success that has so far eluded their expensively-assembled, uber-talented squad - their hunger only deepened by the 1-0 loss to Chelsea in last season's final.
Such appetite was on full display in Portugal's capital in a showcase of all that that is good about Guardiola's team - effort, awareness, patience and precision combining to lay the foundation for untouchable attacking excellence.
Mahrez's early goal - awarded after a very lengthy VAR delay - burst the bubble of the home side, who were then simply dismantled, most notably and painfully by a former employee of their fiercest rivals.
Silva is a magician of a footballer, doing the simple things relentlessly well but also making the ridiculously hard look routine.
Few players can rifle a rising ball in on the half-volley as he did in the 17th minute, with a dramatic cannon off the underside of the bar an aesthetic bonus.
"I always tell him 'you are the perfect player'," added Guardiola. "With the ball he is more than exceptional, but I always say to him you have to score goals, go and win games, you have to have the ability to do it.
"He scored one of the best goals I've seen for the technique, for everything.
"This was his home town, and he loves coming back here. Of course he is a former Benfica player, so this was special for him tonight."
In any other game, Sterling finding the top corner with a precise curling shot to go joint second with Paul Scholes on the list of leading English goalscorers in the Champions League with 24 would make more headlines. But not this one.
As a telling comparison of City's growing authority, their efforts in Lisbon made them the first team to score as many as four goals in the first half of a Champions League knockout tie since Bayern Munich beat Barcelona 8-2 in the last eight en route to winning the trophy in 2020.
There was precious little Sporting could do to stem the tide, their fans left only to offer sporting applause to City's brilliance as the goals rained in.
However, while teams have been blown away this season without ever laying a glove on City, Ruben Amorim's side at least provided small glimpses of what they are about with short periods of neat passing and well-worked but ultimately fruitless openings down the flanks.
Sporting have made giant strides both on and off the field in the past two years to unite again after the training ground attack by hooligans in May 2018 and to once again compete for silverware.
As a sign of the progress made, their players left the field to applause, singing and twirling scarves from a loyal, appreciative support who stuck by their side until the very end.
As for City, last year's final defeat still rankles and they may well never have a better chance to win it than this year.
'A winnable competition for Man City'
Former England goalkeeper Rob Green, speaking on BBC Radio 5 Live:
It is looking like this is a very winnable competition for Manchester City this season.
What Pep had done is incredible, the way he has transformed the whole club.
They had success before but not to this level and you will see Man City fans who will say he is amazing even if he doesn't win the Champions League.
But, for him, it is there and he would love nothing more to go and win this competition.