"Lacazette is simple. In every game he is stronger since he has joined us", Wenger said.
The France worldwide joined Arsenal for a club-record £52million transfer from Lyon this summer, and has made an immediate impact by heading in an early goal against Leicester City.
The subs paid off, with Ramsey scoring in the 83rd minute to make it 3-3 and Giroud heading in off the post two minutes later to win a thrilling encounter for Arsenal.
But after deciding to stick it out for a sixth season at Arsenal, Giroud was the north London club's match-winner on the opening day of the new Premier League campaign after coming off the bench.
Just a few minutes later, he would net the goal that would secure the win for Arsenal to start the season. He's a fantastic player, but as well he has a big weight in this squad.
"Once again, we had to come back and the team showed it was very well prepared because it could cope with the unpleasant situation", said Cech.
The arrival of Alexandre Lacazette will likely relegate Giroud to the status of a benchwarmer this season but the 30-year-old proved his worth with a towering header in the 85th minute.
"At one stage I opened the door for him as I knew I had many strikers, and in the end he chose to stay".
"It was a relief Giroud chose to stay".
Obviously, with this being the first game of the season, Arsenal is going to be top of the table for at least the next 12 or so hours until the rest of the Premier League plays on Saturday.
Nigerian global, Kelechi Iheanacho, came on for his Premier League debut for Leicester but was unable to help the Foxes avoid defeat.
Leicester four minutes later replied with a goal by Okazaki, and then Vardy reminded of themselves by 29 minutes, one of the main creators of championship success, "Leicester" rounded out a flawless cross from Albrighton.
After the victory, the Arsenal boss was quick to praise his team and the impact Lacazette made on his Premier League debut.