Olivier Giroud headed home the late victor on Friday.
Jamie Vardy then struck twice, either side of a Danny Welbeck equaliser, as the 2015-16 champions looked for a first league win over Arsenal since 1983.
Vardy scored again in the second half before much-maligned manager Arsene Wenger would make two critical substitutions, bringing in striker Olivier Giroud for Rob Holding and Aaron Ramsey to replace Mohamed Elneny with just over 20 minutes left in the game.
Arsenal welcomed Leicester City into Emirates Stadium on Friday to get the festivities rolling this season, and it appeared as if everyone would get a chance to use their Arsenal jokes for at least the next week.
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Record signing Alexander Lacazette opened his account within two minutes of the kick-off, but the home side's lead was nearly immediately rubbed out as Shinji Okazaki equalised minutes later before Jamie Vardy put the visitors in front after half an hour.
The pressure eventually told as, in the space of two minutes late on, Ramsey controlled Granit Xhaka's pass and smartly tucked past Schmeichel, before fellow sub Giroud headed in off the bar from a corner to earn maximum points for his side.
Asked if Giroud could still leave before the transfer window closes on August 31 until January, Wenger replied: "No. It was a relief for me he made a decision to stay". But I don't want him to go and in the end he chose to stay.
To think, we have an entire opening weekend to go yet, as well as an entire season. But Leicester, which so astonishingly won the league in 2016, couldn't hold on for its first win at Arsenal since 1973.
"We were quite good previous year on corners and I believe with a bit of work, we can get that out of the system".