Cole Palmer scored four times in Chelsea's 4-2 win against Brighton and Hove Albion in the Premier League Saturday.
Arsenal moved level on points with Manchester City with a last-gasp 4-2 win against Leicester City.
At Emirates Stadium, Gabriel Martinelli put Arsenal ahead in the 20th minute with his first goal this season, the Brazilian winger drilled a low finish inside the far post from Jurrien Timber's cross.
Martinelli turned provider on the stroke of half-time, setting up Leandro Trossard to stroke in Arsenal's second goal.
James Justin reduced the deficit with a deflected 47th-minute effort and stunned the Emirates Stadium into silence in the 63rd minute when his thunderous volley cannoned in off the woodwork.
But Mikel Arteta's men stole the points four minutes into stoppage-time when Trossard's shot deflected off Leicester's Wilfred Ndidi for an own goal, with Kai Havertz netting moments later to confirm the victory.
Palmer became the first player ever to score four goals in the first half of a Premier League match with a stunning display at Stamford Bridge.
Former Brighton duo Moises Caicedo and Robert Sanchez were guilty of mistakes when Georginio Rutter put the Seagulls ahead in the seventh minute.
Just moments after hitting the post and then having a goal disallowed, it was third time lucky for Palmer in the 21st minute.
Palmer equalized with a clinical finish after Nicolas Jackson seized on Adam Webster's mistake to tee up his fellow forward.
When Jadon Sancho was tripped in the area by two Brighton defenders, there was never any doubt that penalty expert Palmer would step up to dispatch the 28th-minute spot-kick with ease.
Palmer completed his nine-minute-and-48-second treble in the 31st minute, curling a brilliant free-kick past Bart Verbruggen from 25 yards to make it five goals in six league games this term.
Carlos Baleba pulled one back in the 34th minute, but Palmer's incredible afternoon was not over and, in the 41st minute, the England star converted Sancho's pass with an emphatic strike.
West Ham United midfielder Tomas Soucek rescued a 1-1 draw at Brentford, who made Premier League history thanks to Bryan Mbeumo's quick-fire opener.
Under-fire Hammers boss Julen Lopetegui saw his side fall behind after just 37 seconds as Mbeumo's superb volley made Brentford the first Premier League team to score in the first minute in three consecutive games.
But Soucek swept in West Ham's 54th-minute equalizer to avoid a fourth defeat in their last five games in all competitions.
Dwight McNeil struck twice in the second half as Everton beat Crystal Palace 2-1 to end their winless start to the league season, just days after the Goodison Park takeover by a group led by American billionaire Dan Friedkin.
Raul Jimenez's 51st-minute penalty gave Fulham a 1-0 win at Nottingham Forest.
Liverpool will go top of the table if they win at Wolverhampton Wanderers in Saturday's late game.
RESULTS
Forest 0 Fulham 1 (Jimenez 51-P)
Chelsea 4 (Palmer 21, 28-P, 31, 41) Brighton 2 (Rutter 7, Baleba 34)
Brentford 1 (Mbeumo 1) West Ham 1 (Soucek 54)
Everton 2 (McNeil 47, 54) Palace 1 (Guehi 10)
Arsenal 4 (Martinelli 20, Trossard 45+1, 90+4, Havertz 90+9) Leicester 2 (Justin 47, 63)
