Giroud's clever header in the 85th minute secured the points after Lacazette had taken just 94 seconds to make his mark with a header from Mohamed Elneny's curling cross, equalling the record for the fastest opening goal in a Premier League season.
But Wenger revealed after the dramatic clash that Giroud "decided to stay" at the Emirates and he is "really loved" at the club.
Giroud, 30, started just 11 Premier League matches last season and scored 12 goals.
Lacazette can integrate well into the game we want to play with his movement, combination, technical quality and efficiency, Wenger told Sky Sports. "I know how important he is not only as a player but also in the group". Yes, they've lost some players too, but they still have the prolific Sergio Aguero and have a squad capable of challenging in the Premier League and Champions League. "As a game is in 90 that would guarantee you a goal (in every game)".
Ex-Manchester City star makes bold prediction about Manchester United
They have been far too reliant on Troy Deeney for goals. "The club was clever like that because we anticipated what we needed". That's why it's great to be here'. "We spoke and I saw last season how tough is this league".
The 23-year-old England international has struggled to secure a regular place since arriving at Arsenal six years ago, but Wenger believes the winger has the potential to become a great player.
"I can't tell you that at the moment", he said.
Asked if he expected Al-Khelaifi to get in touch, Wenger replied: "No, no. I think if you read the French papers, they are on Mbappe's case to finish their transfer market".
Premier League 2017/18: Top 10 new signings to watch out for
This should also be the season for John Stones , who certainly didn't do what he was bought to do last season. The squad depth is good for rotation, so their involvement in other competitions shouldn't be a problem.
One of those was from playmaker Alex Oxlade-Chamberlain who, from the start, played the game with an attacking mentality and created a number of incredible chances.
"I suppose for Arsenal the big question is when Sanchez comes back, is he a replacement for Sanchez?"
Was Lady Stoneheart in the latest episode of Game of Thrones?
Season 1 ended with the death of Ned Stark, arguably the show's central character up until that point. There may be a "ghost" hanging around Winterfell , and we're not talking about Jon Snow's direwolf.
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