Guardiola hails 'back to business' Haaland after Man City rout Wolves
Arsenal's 3-0 win over Bournemouth earlier on Saturday had opened up a four-point lead for the Gunners.
But City showed no signs of feeling the pressure as they cut the gap back to one point and have three matches remaining to Arsenal's two.
Haaland has faced criticism for not matching the standards of his stunning first season in Manchester, when he scored 52 goals as City won the treble.
However, the Norwegian took his tally for this season to 36 goals in 41 appearances with a devastating display of finishing.
"Erling is back to business," said City boss Pep Guardiola.
"Penalties are a guarantee but the second and fourth (goals) were unbelievable."
Haaland was restored to Pep Guardiola's starting line-up after coming off the bench to score against Nottingham Forest last weekend on his return from injury.
However, Guardiola pointed to an earlier injury problem this season that kept him out for two months as the reason behind Haaland failing to hit the same heights as last year.
"He was injured, an important one, and he’s so tall to get back to your best form you need time," added Guardiola.
Even if City collectively are also not at the same level as a year ago, the remain well on course for a Premier League and FA Cup double.
The defending champions travel to Fulham and Tottenham in their next two games before hosting West Ham on the final day of the season.
And Guardiola insisted they will need to win all three matches, despite Arsenal facing a tricky trip away to Manchester United next weekend.
"One week, three games. Nine points we will be champions, six or seven points, Arsenal will be champions."
Wolves had inflicted one of City's just three Premier League defeats this season.
But the visitors were blown away as Guardiola's men extended their unbeaten home streak to 43 games.
Josko Gvardiol was wiped out by Rayan Ait-Nouri for the first of two City penalties and Haaland sent Jose Sa the wrong way to open the floodgates on 12 minutes.
The City striker then rose highest to power home a header from Rodri's hanging cross to the back post.
Haaland looked set to complete his hat-trick when he raced through in first-half stoppage time only to be clipped by Nelson Semedo.
Referee Craig Pawson initially waved play on, but overturned his decision after a VAR review.
Haaland showed no mercy to fire home his second hat-trick in as many appearances against Wolves at the Etihad.
25 goals 'not bad' for Haaland
Any suggestion City could rack up a huge score to chip away at their goal difference deficit compared to Arsenal was punctured as Wolves pulled a goal back early in the second period.
Hwang Hee-Chan swept into an unguarded net after Ederson flapped at a cross.
Yet, City's three-goal cushion was restored in spectacular fashion within a minute.
Phil Foden's long ball picked out Haaland, who cut onto his lethal left foot and found the top corner.
Haaland's four-goal haul looks to have settled the race for the Golden Boot as his 25 Premier League goals are now five more than Alexander Isak and Cole Palmer.
"Twenty-five goals (is) not bad," said Haaland. "We’ve got a not so bad manager who pushes me.
"I try to develop every day. I had some problems (this season) but let’s not focus on them. We’ve got four finals left for our season."
There could even have been more for City's number nine, who has twice before scored five in one game since arriving in England.
Sa made a spectacular save to deny Haaland matching that feat once more.
And the 23-year-old was left less than impressed with Guardiola's decision to hand him a rest for the final eight minutes when he was replaced by Julian Alvarez.
It was Alvarez who rounded off the scoring by finding the far corner from Rodri's pass five minutes from time.
Defeat ends Wolves' hopes of European football next season as they remain 11th.