Arsenal showed an immense amount of determination to hold onto a 1-0 win over Wolves at Molineux.
The Gunners went ahead in the first-half thanks to a close range goal from Brazilian defender Gabriel.
But the away side saw themselves a man down when Gabriel Martinelli was shown a bizarre red-card.
The Brazilian attacker was shown two bookings at the same time for infringements seconds apart - stopping a throw-in and a foul on Chiquinho.
Lacazette had an immediate chance to double Arsenal's lead but sprayed his shot wide.
Mikel Arteta replaced the Frenchman with Rob Holding and set up a deep low block.
Aaron Ramsdale was immense late on as he denied Romain Saiss and Leander Dendoncker, while Chiquinho had a shot blocked on the line.
Arsenal have now leapfrogged Manchester United into fifth and sit one point behind West Ham United with two games in hand on the Hammers.
Speaking after the game, Lacazette told BT Sport: "This meant a lot and we showed a lot of good things for the rest of the season.
"It's always stressful in this kind of game. I'm proud of my team because we handled it well [being down to 10 men]."