The Chile forward landed heavily in the cameraman's area on the touchline during an incident in the first half and was later forced off with a hamstring injury.
With Sanchez now likely to be sidelined for a number of weeks, Wenger defended his decision to play the 26-year-old in the 1-1 draw against Norwich on Sunday.
Having felt his hamstring after the Champions League victory over Dinamo Zagreb, Wenger said all of the club's medical tests showed he was in peak fitness to start at Carrow Road.
While the Frenchman said he is happy to take the blame for the number of injuries being accrued by his squad - he also pointed to Sanchez being pushed into the camera area as a potential reason for this latest blow and feels it could have been worse for the former Barcelona man.
"First of all it's dangerous to have a camera there," Wenger said.
"He could have killed him
Secondly, he (Bennett) didn't need to push him like he did
I think the camera position was absolutely dangerous.
"When he was pushed into the boards on the side of the field that did not shock anybody
That injury can come from that as well
I'm not expert enough to know but if you want to blame me I'm okay with it."
Bennett tweeted after the match to give his side of the incident, writing: "Genuinely was trying to stop not push Sanchez just to clear that up."
By the time Sanchez then limped out of the contest in the second half, Arsenal had already lost Laurent Koscielny to a hip injury while Santi Cazorla was playing on despite taking a blow to his knee.
Wenger admitted after the game the Spain midfielder had been "playing on one leg" but backed his decision to leave the 30-year-old on the pitch despite some problems with his mobility.
"It could be a rupture," Wenger said.
"What happened to Cazorla, is that the ball was in the air, he wanted to pick the ball out, and he didn't see Gary O'Neil who came in and went through him.
"I don't know more than you
I have to wait until we have a complete assessment from the specialist
We know his external knee ligament has been touched
He might have a capsular problem as well, but I don't know for how long he will be out.
"He was even booked for diving when his knee let him down, because he could not change direction
He wanted to cut back.
"I don't understand how he carried on
I saw he was not himself, like he was against Spurs and he was dizzy
I could see he was not completely but every time I said Santi are you alright, he said he was OK
He loves so much to play."
While it is only speculative at this point, Wenger conceded it was possible Cazorla could be sidelined until March but still retains hope that it could be much sooner than that.
It is understood the player has returned to Spain for treatment on his exterior collateral ligament - with the situation surrounding whether an operation is required still unclear.
With a number of players still absent, the timely return of Theo Walcott will boost Wenger's options for Saturday's visit of Sunderland.
The fixtures over the festive period come thick and fast but Wenger is adamant he will not rush back any of his missing players to fill holes in his side.
"I will not take that gamble," he added.
"A player who comes back goes always through a period where the reconstruction of the muscle takes longer than the time where they don't play.
"There is always a risk when a player has been out for five weeks that in the first two or three weeks he has a recurrence of the injury because nobody can tell you the risk doesn't exist."
Source : PA