The Gunners, who sit in fifth place in the Premier League, travel to White Hart Lane on Sunday four points behind Spurs, who are in third, while fourth-place Chelsea hosts West Brom.
Many have labelled the clash as a must-win for Wenger's men, including midfielder Santi Cazorla; however the manager will have to do without his first-choice right back Sagna, who remains out with the knee injury that saw him miss the club's last match with Aston Villa.
"[Sagna] is not ready for Sunday," Wenger told the club's official website. "It is too short for him."
Wenger also indicated that left back Kieran Gibbs is still not ready to return from a thigh problem, while Abou Diaby, who is suffering from a calf complaint, will face late tests.
"Abou is an uncertainty," Wenger said. "He has a calf problem, a minor one. It is question of days. He will have tests and then we will see if we can use him on Sunday or not. It is a 50-50. Actually maybe a bit more for him playing.
"Kieran is not back. That was as we expected."
Carl Jenkinson is expected to play at right back, while Nacho Monreal should continue on the left.
Arsenal will be looking to replicate the form that saw the club defeat Spurs 5-2 at the Emirates earlier in the season, although the Gunners were helped by an Emmanuel Adebayor red card.