A first-half blitz, inspired by the excellent Ilkay Gundogan, saw City go into the break 4-0 up.
Gundogan (2), Joao Cancelo and Riyad Mahrez ended the game as a contest before half-time, with Raheem Sterling bagging a fifth before an hour had been played.
The Baggies managed to play out the last half-hour without conceding again, but it will be little consolation to Sam Allardyce whose side remain in deep trouble near the foot of the table.
West Brom were out of the blocks and in City’s faces for the first couple of minutes, launching throw-ins into a crowded box and looking dangerous enough to cause a few hurried hacks clear.
But having weathered the storm, City almost scored with the first attack as Bernardo worked himself space before finding Phil Foden who hit a low angled shot took a slight deflection and then was brilliantly fingertipped on to the foot of the post by Sam Johnstone.
Surely Johnstone, who almost single-handedly kept City at bay in the 1-1 draw at the Etihad last December, couldn’t again be our nemesis?
Three minutes later, he was beaten by a shot that left him rooted to the spot as Joao Cancelo picked out Ilkay Gundogan on the edge of the box and the in-form German shifted the ball to the left before striking a sublime shot into the bottom left-hand corner to put City ahead.
It was Gundogan’s seventh of an excellent season – already the best seasonal tally of his career.
City were moving the ball around with such fluidity, it seemed more goals were inevitable but when the second did come on 20 minutes, it was greeted in almost total silence and no celebration.
Bernardo collected the ball on the right and shortly after, the flag was raised for offside, but with no whistle to stop play, Bernardo picked out Cancelo on the edge of the box and the Portuguese curled a beauty into the top left corner.
With offside called, VAR then checked to see if Bernardo had been offside – but replays proved he marginally was onside – so the goal, which was a beauty, was awarded – perhaps the most socially distanced celebration ever?
And the first-half kept getting better for City as Gundogan made it 3-0 with another fantastic effort.
This time, the German midfielder created his own opportunity, winning the ball on the edge of the box, taking past a defender before drilling a low shot into that left-hand corner again.
It was sublime stuff from City, who have so many players playing at the top of their game just now.
And the best 45 minutes of the season was completed in first-half added time as Raheem Sterling spotted Riyad Mahrez on the right of the box and the Algerian instantly controlled the ball, shifted inside of a challenge before drilling a fierce drive into… you guessed it – the overworked left-hand corner of the net.
Bias apart, it was a joy to watch and as one celebrated fictional sports commentator might claim, ‘liquid football’.
City carried on where the first-half ended, with Rodri thumping he crossbar from 25 yards before the fifth of the evening came just before the hour.
Rodrigo picked out Mahrez on the right and the Algerian's delightful first-time cross meant Sterling needed only tap the ball into the net from a couple of yards out.
City declared at five with the hard work done in the first-half.
And all without Kevin De Bruyne and Sergio Aguero - what a performance.
What it means…
City move to the top of the Premier League officially for the first time this season.
After shifting through the gears over the past six weeks or so, City tonight sit at the summit, seven points clear of Liverpool with the same games played.
United will return to the top if they beat Sheffield United tomorrow evening, but on this evidence, this City side look every bit as good as the all-conquering class of 2018/19 – though there is a long way to go – half a season, in fact.
City take on Sheffield United at the Etihad on Saturday afternoon, kick-off 3pm.
Following that are trips to Burnley a week on Wednesday (6pm kick-off) and Liverpool on the Sunday after that (Feb 7, 4.30pm kick-off).
Cancelo’s ever-growing influence
You only have to look at his cameo against Cheltenham Town at the weekend to understand how highly Pep Guardiola rates the Portuguese.
In that game, it was his superb pass that played in Phil Foden for the equaliser and he also had a big hand in the third and final goal of the game – all in the space of a few minutes.
Tonight, he assisted Gundogan’s opening goal with a sumptuous pass and then, when many had stopped for the assistant referee’s flag, he saw the phase through with a delightfully placed shot into the top left corner.
Pep Guardiola recently said that he thought Cancelo maybe didn’t know how good he actually is – on this evidence, he soon will.
Star man: gundogan
Another two goals and an hour of brilliance just edges the vote for our German star. Joao Cancelo and Riyad Mahrez pushed him hard, though.
City: Ederson, Cancelo, Zinchenko, Dias, Stones, Gundogan (Laporte 52), Rodrigo, Foden (Torres 52), Bernardo (Jesus 60), Sterling (c), Mahrez
Unused substitutes: Steffen, Walker, Mendy, Fernandinho, Garcia, Bernabe
West Brom: Johnstone, Furlong, Gibbs, Ajayi, O'Shea, Robinson (Bartley 46), Livermore, Pereira, Sawyers, Snodgrass (Phillips 60), Grant (Robson-Kanu 64)
Stats and facts:
- City have now won seven Premier League -matches in a row and 11 successive victories in all competitions, their longest streak since an 11-match sequence from August to October 2017.
- City have kept 11 clean sheets in 19 league games this season - only in 1976-77 have we reached double figures in fewer matches.
- City's current seven-game Premier League winning run at West Brom is our longest in the top flight against a single opponent.
- Phil Foden has now played 100 games in all competitions for City.
- With eight goals this season, Ilkay Gundogan is enjoying the best scoring campaign of his career.
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