The Emirates Stadium had many empty seats for the top-flight clash, which the Gunners won thanks to a brace from Pierre-Emerick Aubameyang and a penalty converted by Alexandre Lacazette, and
Wenger reckons it's understandable considering the club's failure to challenge for the title.
"We know that before the game, and [the fans] know as well that we don't go for the championship. That's the price we have to pay for that," he told Sky Sports.
"It's the fact that in the table, when you look, there's not a lot to win. Especially as well, we play before a big game, so the mind is maybe not completely there.
"And the fact that the players broke up [for internationals] and got back together. The weight of these ingredients, I don't know.
"It was a game I feel mentally first half we were not in the pace of the game, we were a bit sloppy, lacked cohesion. We missed the basic ingredients that makes football great - to play with power and enthusiasm.
"Really to me, it was a lack of urgency, but in the second half, it was a lot better. In the first half, I always thought we could lose this game, but in the second half I always felt we could win this game."
The Gunners are sixth in the league standings, 13 points below the top four and five adrift fifth-placed Chelsea.
Wenger reckons it's understandable considering the club's failure to challenge for the title.
"We know that before the game, and [the fans] know as well that we don't go for the championship. That's the price we have to pay for that," he told Sky Sports.
"It's the fact that in the table, when you look, there's not a lot to win. Especially as well, we play before a big game, so the mind is maybe not completely there.
"And the fact that the players broke up [for internationals] and got back together. The weight of these ingredients, I don't know.
"It was a game I feel mentally first half we were not in the pace of the game, we were a bit sloppy, lacked cohesion. We missed the basic ingredients that makes football great - to play with power and enthusiasm.
"Really to me, it was a lack of urgency, but in the second half, it was a lot better. In the first half, I always thought we could lose this game, but in the second half I always felt we could win this game."
The Gunners are sixth in the league standings, 13 points below the top four and five adrift fifth-placed Chelsea.
