Diaby doubtful for Spurs showdown
The midfielder has been struggling with a calf injury that saw him substituted in the 2-1 win over Aston Villa and he will be assessed ahead of the game at White Hart Lane.
Wenger also confirmed that Bacary Sagna and Kieran Gibbs will miss out as they continue to battle problems of their own.
Sagna has been troubled by a knee complaint that saw him replaced by Carl Jenkinson against Villa, while Gibbs is working his way back to fitness after a thigh injury.
"Abou is an uncertainty. He has a calf problem, a minor one. It is question of days," Wenger told the club's official website.
"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.
"(Sagna) is not ready for Sunday. It is too short for him. Kieran is not back. That was as we expected."