After a slow start to the season which saw Spurs lose to Manchester United before surrendering leads in the following two games, the Lilywhites have kept three consecutive clean sheets and picked up seven points in the process.
A convincing Europa League win over Qarabag was sandwiched in between those results, and Wenger is aware of the challenge his side will face in midweek.
"They had a slow start but since then they have had two good wins, so that will have boosted their confidence," he said, in quotes published by talkSPORT.
"It makes you think it will be a very even game tomorrow."
The meeting is set to bring about a host of changes from both sides, with the weekend’s Premier League fixtures given priority.
Spurs have been dealt a blow, however, with Ryan Mason, Nabil Bentaleb, Mousa Dembele and Alex Pritchard all unavailable - as announced on the club's official website - meaning Mauricio Pochettino may have to include more ‘first-teamers’ than he would have desired.
Arsenal aren’t without their own problems, despite seeing Gabriel's red card against Chelsea rescinded, with the suspended Santi Cazorla adding to the absentee list after Francis Coquelin’s knee injury, rendering both teamsheet announcements full of intrigue come 6:45 PM tomorrow.