Olivier Giroud, meanwhile, starts from the bench as Lacazette received the nod from Wenger to start the season as first-choice centre-forward.
"It was one of the great days".
Pushed on whether he thought Giroud could leave before the transfer window closes on August 31, Wenger replied: "No".
"I rate him as a player but we have similar types with Alex Iwobi, Jack Wilshere back, Mesut Ozil - we have plenty of the same type of players". He's a fantastic player, but as well he has a big weight in this squad.
Giroud, who had a hard time getting into the starting XI last season as Wenger preferred to play Alexis Sanchez as the lone striker, has been vocal in his desire to play more games from start.
"We had some avoidable goals which we conceded and overall we have to work on that", he said referring to poor marking in the by his team's defence.
Lacazette almost had his second of the night just minutes later, but Leicester keeper Kasper Schmeichel turned the shot aside, but Giroud beat the Dane with an exquisite header on the ensuing corner to give Arsenal the 4-3 victory.
Man Utd return to negotiating table for Inter Milan ace Perisic
Spalletti's claims add further weight to remarks he made last month that United's deal for Perisic was dead in the water. Jose Mourinho has said Inter Milan "put up a good defence" as Manchester United sought to sign winger Ivan Perisic .
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The market also awaited U.S. consumer inflation data on Friday that would offer more clues about the pace of the U.S. Ongoing global glut concerns lingered in oil markets despite a bigger-than-expected draw in USA crude inventories.
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And things are kind of working out now, I feel like I've got a pretty good downhill plane when throwing fastballs and changeups. Jose Bautista shifted from right field into the DH role, while Ezequiel Carrera was entered into the outfield.
Arsenal staged their fightback after Okazaki came off in the 72nd minute.
But the Gunners rallied right until the very end and substitutesRamsey and iroud turned the game on its head in the final 10 minutes.
"You come away from home, score three goals and are almost there and then concede two.bitterly disappointed", he said.
"We're disappointed to score three and come away with a defeat", said Leicester manager Craig Shakespeare. He has scored seven Premier League goals as a substitute since August 2016; three more than any other player.
Shakespeare was true to his word and started Riyad Mahrez despite the Algeria global asking to leave the King Power Stadium.
Leicester showed some of the form that won them the title in 2016 and helped stave off relegation last term but in the end they were undone by canny France global Giroud who has been linked with a move away from Arsenal all summer.
The Serie A side have now said they will not increase their offer and Shakespeare is happy to have Mahrez in the team.
Asked whether Mahrez would be at the club when the window closes, Shakespeare said: "Who knows?"