Haaland was withdrawn at half-time of the 3-1 win, having laid on Ilkay Gundogan’s second goal, to prompt fears over his fitness.
The striker collided with Villa goalkeeper Emi Martinez earlier in the game, with Sky Sports suggesting a hamstring injury.
Speaking to reporters after the game, Guardiola confirmed: “Haaland had a knock, he was uncomfortable. At 3-0 we don’t want to take risks.
“We’ll see and assess in the next days. If he is not ready, we play another one. Hopefully, he’s ready but we will see.”
City goalscorers Gundogan and Rodri warned their team-mates of the task they face against the Gunners, with or without Haaland.
Gundogan told Sky: “The three points today help but it will be a completely different game [against Arsenal].
“It will be a tough game with the two best teams in England at the moment.”
Rodri added to BBC: “We have the chance to go top. Go there and show our personality, the team that we are. They are playing at an incredible level and we have an incredible level too.
“It is going to be an incredible fight and an incredible battle and we have the chance to be on top of the table so that’s what we have to think.”