Arsenal secured back to back victories in the Premier League with a 2-1 win over West Ham, but they were made to work hard for the three points by their stubborn visitors.
The Gunners opened the scoring on 25 minutes, when Lacazette powered home a header from an inch-perfect Pierre-Emerick Aubameyang cross. The Hammers equalised on the stroke of half time however, when Michail Antonio poked home from close range following Ryan Fredericks' wicked delivery.
Both teams had chances to win the game in the second half, but it was Arsenal who snatched it late on, with Bukayo Saka cutting the Hammers defence apart before Dani Ceballos' rolled square ball was tapped home by substitute Eddie Nketiah.
Let's have a look at the player ratings from a gruelling evening in north London.
1. Goalkeeper & Defenders
Bernd Leno (GK) - 6/10 - Could do little with the equaliser, and was called into action on a couple of occasions in the first half. Made a huge stop to deny Antonio from giving West Ham the lead.
Rob Holding (CB) - 6/10 - Allowed Antonio to dart in front of him for his goal and found the forward's power and presence hard to handle.
Gabriel (CB) - 8/10 - Another extremely solid display by the new signing, as he continues to adapt seamlessly to English football. An elegant mountain at the back.
Sead Kolasinac (CB) - 6/10 - Came in to replace Kieran Tierney, but was caught out on Fredericks' cross from the right. Not a natural centre-back and it showed.
Hector Bellerin (RM) - 6/10 - Didn't quite give Arsenal the edge they were looking for on the right-hand side, but hugged the touchline in search of possession.
Dani Ceballos (CM) - 8/10 - Best midfielder on the pitch. Harassed the Hammers, threw himself into heavy challenges and still had the energy to play his usual pretty stuff. Got the assist for the winner. A quality player.
Granit Xhaka (CM) - 7/10 - Offered his vintage work ethic and defensive cover, but occasionally lacked ambition going forward. Drove his team over halfway countless times though.
Bukayo Saka (LM) - 7/10 - Allowed the Hammers in behind down his flank to score, but constantly looked to take on his full-back at the other end. Nice play in the buildup to Arsenal's second.
Willian (RW) - 6/10 - Prodded and probed the backline, running at his full-back and pulling back some nice crosses for players lying in wait. Not at his best, however.
Alexandre Lacazette (ST) - 7/10 - Opened the scoring with a powerful and wonderfully-placed header, and led the line superbly. Stretched West Ham's backline and made space for his fellow forwards.
Pierre-Emerick Aubameyang (LW) - 7/10 - Put Lacazette's goal on a plate for the Frenchman, and led the charge from his wide-left position. Classy as always.
Nicolas Pepe (RW) - 6/10
Eddie Nketiah (ST) - 7/10
David Luiz (CB) - N/A
5. Goalkeeper & Defenders
Lukasz Fabianski (GK) - 6/10 - As reliable a keeper as you can find at this level. Stood little chance in preventing either goal, but marshalled his troops well.
Ryan Fredericks (RB) - 6/10 - Always going to be a tough evening against Aubameyang, but made his mark in the opponents' third, delivering a killer cross to supply the opening goal.
Issa Diop (CB) - 6/10 - Another unconvincing defensive display by Diop. Looked lost in the backline and couldn't contain the Arsenal forwards. Coped better in the second half.
Angelo Ogbonna (CB) - 6/10 - Seemed to relish the physical battle with Lacazette, and did his best to unsettle the Frenchman. Solid, uncompromising and impressive.
Aaron Cresswell (LB) - 7/10 - Tucked inside to act as a third centre-back at times, and got stuck into his duel with Willian. Came out on the losing side occasionally, but did his best to stop the flow from the Arsenal right.
Jarrod Bowen (RM) - 6/10 - Full of energy and determination. Neat footwork and always willing to get in behind. A tough evening.
Tomas Soucek (CM) - 6/10 - Battled hard to stop Arsenal from breaking and running at the defence. Set West Ham in motion for the equalising goal. Rattled the crossbar with a powerful header.
Declan Rice (CM) - 7/10 - Kept West Ham ticking with some crisp passing and biting challenges. Showed why he's so highly rated.
Arthur Masuaku (LM) - 7/10 - Sat deeper in his left-sided role and covered the flank nicely. Supported Cresswell in his containment of Willian. Offered plenty of pace and a willing outlet on the left side.
Pablo Fornals (CAM) - 5/10 - Flitted in and out of the game and looked short of creativity - which is an issue, as that is his job.
Michail Antonio (ST) - 7/10 - Leading the line away at a bigger club is a thankless task, but Antonio did it excellently. Constantly ran in behind and across the defence, got his reward with some excellent movement to poke home the equaliser.
Andriy Yarmolenko (RM) - 6/10
Sebastien Haller (ST) - N/A
Felipe Anderson (LM) - N/A