The striker, who the Gunners signed from Lyon for an initial fee of €53 million in the summer, finished clinically to put the hosts ahead after two minutes, expertly heading home Mohamed Elneny's cross.
It didn't take long for things to get started, with Alexandre Lacazette giving Arsenal the lead in just the second minute of his debut as the most expensive signing in the history of the club.
While Lacazette's goal was fantastic, it resulted in a number of other players' efforts being overlooked and unrecognised.
"We'll go back to the training ground and reflect on the type of goals we scored and the game plan".
The 23-year-old used fantastic pace and impressive technique to regularly have a go at striking the target, but was unsuccessful.
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. "Because Giroud is in his prime and is at the top of his game".
He said: "At some stage it didn't look like we'd win". It was a relief for me he made a decision to stay.
"Kolasinac is a good player, he has an attitude that is suited to the premier league, that means hes determined, aggressive, forceful and he wants to play". At the moment sitting here, of course I have a dejected dressing room but to come here and score three has to be pleasing in some respects, but it doesn't feel like it at the moment. "You want the Premier League to be the best league in the world and I think it has to produce this kind of games to produce interest and quality", he said.
Arsene Wenger has told Arsenal fans that he is still on the lookout for one more "exceptional" player in the summer transfer window.
"The spirit of the team was absolutely outstanding, we were punished on every single mistake by a Leicester team who was very efficient", he added.
Remember that boring 2016-17 Premier League season that Chelsea won easily? "First game of the season we played a classic, so for everybody at home it will have been incredible to watch".