Carlos Tevez scored for the first time in 11 months as Manchester City sparked back into life to keep their faint title hopes alive tonight.
Sergio Aguero struck twice and David Silva was on target in a routine defeat of West Brom as City, perhaps belatedly, showed why they were once firm favourites for the Premier League crown.
Manchester United's failure to beat Wigan meant the gap at the top was cut to five points, and with a derby to come the game may not yet be up, but it could still be too little too late.
City suffered an apparently fatal blow to their title chances as they slumped to defeat at Arsenal on Sunday but they lived up to promises to go down fighting as they returned to the Etihad Stadium.
For much of the game they were a side far removed from the tension-ridden one of recent weeks and played much more like the carefree team they were in the autumn.
City were without injured lynchpin Yaya Toure while the suspended Mario Balotelli was present only in an executive box.
Tevez's first start since his much-publicised dispute with the club gave the side a different look while West Brom, making five changes after manager Roy Hodgson claimed they were virtually safe, offered little.
They was a further change in the middle as referee Lee Mason, involved in controversy in United's weekend win over QPR, was replaced by Kevin Friend.
City began well with Aguero breaking into the box in the opening minutes and cutting back, only to have his shot blocked.
The opener came after just six minutes as Aguero collected the ball midway inside the West Brom half and ran diagonally towards goal before lashing in a low shot past Ben Foster from 25 yards.
City looked back to their best as Aguero and Samir Nasri combined to set up Tevez, but he blasted over.
The fit-again Silva, whose outstanding early season form has tailed off in recent months, then skipped into the area and beat Foster only to get in a tangle with Tevez.
Silva linked better with Tevez moments later but Foster parried his close-range shot.
Micah Richards should have doubled the lead just after the half hour as he timed his run onto Tevez's pass perfectly and cut back to shoot past Foster, but Craig Dawson blocked on the line.
Graham Dorrans shot straight at Joe Hart as West Brom made a rare foray forward but City began to slow as the first half wore on.
Tevez turned nicely to release Silva but the Spaniard was caught and it was not until after the interval City regained their zest.
Nasri volleyed wide from a Silva cross soon after the restart and City really started to lift themselves as news filtered through to the crowd that United had fallen behind at Wigan.
City's second came in the 54th minute as Nasri seized on a poor clearance and slipped in Aguero to slide the ball past Foster.
It almost immediately got worse for the Baggies as Nasri found space and shot narrowly wide and Youssouf Mulumbu headed an Aguero cross-shot off the line.
Tevez claimed his goal on the hour, the Argentinian finding himself in the right place to tuck home an Aguero cut-back from a Nasri pass.
That proved Tevez's final involvement as he was replaced moments later by Adam Johnson but City continued to pour forward.
A fourth goal duly arrived after Jonas Olsson conceded possession to Aguero and he quickly released Silva, who took the ball in his stride and sublimely chipped the advancing Foster.
After that, City then seemed to put their cue on the rack and play out time.
Edin Dzeko came on for the outstanding Aguero after 73 minutes and much of City's cutting edge appeared to go with the Argentinian.
City seemed happy to wind down the clock safe in the knowledge that victory had been assured.
Nasri attempted to set up Dzeko with a delicate chip in the closing moments but the Bosnian was unable to make the most of the opportunity.