Pep Guardiola has hit back at Roy Keane’s criticism of Erling ­Haaland, calling the Norwegian “the best striker in the world” and said ­Manchester City won the treble because of him last season.

After the 0-0 draw against ­Arsenal, the former Manchester United ­midfielder said that while Haaland’s finishing was the best in the world his general play was “poor” and that he looked like a League Two player.

Related: Manuel Akanji accuses Arsenal of tactical fouling in Manchester City draw

Guardiola, speaking before ­Manchester City’s game against Aston Villa on Wednesday, said: “I am not agreeing with him. It’s like I said: ‘He’s a manager for the second or third league – I don’t think so.’ He’s the best striker in the world and helped us to win what we won last season, and the reason why we don’t create many chances is not because of Erling. We played an exceptional game against Arsenal.

“I reviewed it – we just missed more people in the final third, maybe for the quality and different skills we have. I am surprised it [the criticism] has come from former players. From journalists I understand, because they have never been on the pitch.”

It was pointed out that Keane’s claim was about Haaland’s general play and Guardiola was asked if Julián Álvarez, for example, may offer more in this regard. “You are right, maybe if Julián will be there, Phil [Foden], Kevin [De Bruyne], Oscar Bobb, for example. They like to move in their positions [more],” Guardiola said. “But it is what it is.”

Guardiola said the versatile Dutch defender Nathan Aké will miss the game against Villa and may be out for a prolonged period after limping off on Sunday. “There are two months left so hopefully he will be back soon but I don’t know exactly the timings,” Guardiola said. “For the next games, he will not be ready.”

John Stones may be fit for Villa but Kyle Walker is out and could also miss Tuesday’s Champions League quarter-final first leg at Real Madrid. “The doctors says no but Kyle is Kyle, he has a special genetic [makeup],” Guardiola said.

City are three points behind ­Liverpool and trail Arsenal by one. After the midweek round of matches there are only eight games remaining and the champions need both those above them to drop points to have a chance of retaining the title. Liverpool are at Manchester United on Sunday and when asked if he would be cheering on City’s fierce rival, Guardiola offered a joke. “I always cheer on United,” he said before adding: “No, not really.”

Villa have suffered a blow as their top scorer, Ollie Watkins, is ­unavailable to face City. The England international picked up a hamstring injury during Saturday’s 2-0 win over Wolves. He wanted to carry on after half-time but the doctor advised him not to risk it.

The Villa manager, Unai Emery, said it was a “small injury” but enough to rule him out of the trip to the Etihad Stadium, along with Jacob Ramsey, who has been ­missing since the start of last month with a foot problem.