Liverpool also made a winning return from the World Cup break by beating Aston Villa 3-1 and Harry Kane bounced back from his heartbreak in Qatar by scoring in Tottenham’s 2-2 draw at Brentford.
Arsenal’s momentum towards a first league title since 2004 could have been disturbed by the six-week mid-season break.
But Mikel Arteta’s men passed another test of their resolve after going in 1-0 behind at half-time to Said Benrahma’s penalty.
Two goals in five minutes from Bukayo Saka and Gabriel Martinelli turned the game on its head at a jubilant Emirates before Eddie Nketiah stepped up in the absence of the injured Gabriel Jesus to seal the points.
“I’m delighted with the result and performance,” said Arteta.
“We scored at the perfect time and the crowd was incredible, also in the moment we conceded the goal. They kept on believing. When we scored it got loud and we generated the momentum we needed.”
No stopping Newcastle
Newcastle’s charge towards a return to the Champions League was also not halted by the break as the Magpies scored twice in the first seven minutes at Leicester.
Chris Wood opened the scoring from the penalty spot before Miguel Almiron played a one-two with Bruno Guimaraes and slotted past Danny Ward for his eighth goal in his last eight league games.
Joelinton headed home from a corner in the 32nd minute as Newcastle made it six successive league victories - their best run in the competition since 2012.
“We can do anything,” said Newcastle manager Eddie Howe on the possibility of a title challenge.
“The season is still young enough for all possibilities to exist for us. I want the fans to believe we can do anything.”
In the first Premier League fixture since mid-November, Tottenham were in danger of a damaging defeat after Vitaly Janelt and Ivan Toney put Brentford in command.
But Kane netted with a 65th minute header to start the Tottenham recovery in his first game since missing a crucial penalty in England’s World Cup quarter-final defeat against France.
Brentford have not beaten Tottenham since 1948 and their long wait for a victory over the north Londoners goes on after Pierre-Emile Hojbjerg curled home with 19 minutes left.
Tottenham boss Antonio Conte praised England captain Kane for his contribution following his World Cup disappointment.
“When he came back he was good. We know the importance of Harry for us, his personality, his character. He’s the best player we have. I’m happy that he scored today,” Conte said..
Tottenham stay fourth in the table, four points ahead of fifth-placed Manchester United in the race to qualify for the Champions League.
Liverpool too good for Villa
Liverpool closed to within five points of Spurs and with a game in hand to come by inflicting Unai Emery’s first league defeat as Villa boss.
Mohamed Salah swept home his 15th goal of the season in a frantic opening with chances aplenty at both ends.
The Egyptian then teed up Virgil van Dijk to give Liverpool breathing space before half-time.
Ollie Watkins gave Villa hope with a towering header midway through the second half but Stefan Bajcetic’s first senior goal secured a third consecutive league win for Jurgen Klopp’s men.
At the other end of the table, Everton suffered a damaging 2-1 defeat against relegation rivals Wolves as Rayan Ait-Nouri struck in final seconds for the visitors at Goodison Park.
Everton are now just one point above Wolves in the final relegation place.
“We are in one (relegation battle),” admitted Everton boss Frank Lampard. “We’ve got to fight.”
Fulham won 3-0 at nine-man Crystal Palace, who had Tyrick Mitchell and James Tomkins sent off.
Bobby De Cordova-Reid, Tim Ream and Aleksandar Mitrovic scored Fulham’s goals.
Southampton slipped to the bottom of the table after a 3-1 home defeat against south-coast rivals Brighton.