Mikel Arteta has admitted Arsenal must prove to themselves they have the right mindset to win the Premier League title, but revealed there are major doubts over when Bukayo Saka will return from an achilles injury.

The England forward will miss the second leg of Arsenal’s Champions League quarter-final against Sporting on Wednesday and looks set to be sidelined for Sunday’s crucial Premier League showdown with Manchester City at the Etihad Stadium. Pep Guardiola said after City’s win over Chelsea last Sunday, which cut Arsenal’s lead to six points, that their recent resurgence is “about mindset, not tactics” as he attempts to win a seventh title in England.

Despite losing three of their past four matches in all competitions, Arteta said he has “zero fear” that Arsenal could end the season without silverware again. But he recognised they must show they can cope with the pressure this time after finishing as runners-up for the past three seasons.

“We have to prove that,” he said. “We have proved we have the mindset to do all the things we’ve done up to this point. Now we have to show on the pitch we have the mindset to do that. That’s where we are. We have to prove to everybody, to ourselves.”

Asked how he was feeling after Saturday’s costly home defeat by Bournemouth that left City six points behind with a game in hand, Arteta insisted he is remaining positive. “I’m on fire. I’m on fire,” he said. “Nothing else. I’m dreaming so much. I’ve done so much to be in this position because I know how this club was. I just see beauty, opportunity, and I want to get it done for all these people that have been on this journey with us. And because they deserve it, because it’s been unbelievable.

“That’s what has driven me every single day. I have zero fear. Fear I had when: ‘Oh, if we don’t get this done, this club, I don’t know what is going to happen.’ That was fear. Now, there’s no fear. It’s just purpose, fire, direction and conviction that we’re going to do it.”

Saka has not featured since the Carabao Cup final defeat by City last month and Arteta is not sure when he will return having carried the injury “for a while”. The 24-year-old signed a lucrative new five-year contract in February. “Hopefully, it’s going to be a matter of days and not weeks,” said Arteta. “He has not been able to train much. We want him on the pitch as quick as we can. The moment he can tolerate the load and the pain he has, he will be available and then we will have to see how much he can contribute.”

Arsenal also have doubts over Jurriën Timber, Riccardo Calafiori and their captain, Martin Ødegaard, for the game against Sporting, while Arteta rwill make a late call on Declan Rice’s fitness after the England midfielder missed training on Tuesday.

“He’s played a lot of games, and that’s part of the issue,” he said. “But he’s going to try to do everything that he possibly can to be with us tomorrow. When you come to this stage you want your best players in the best moment and everybody available and that is not the case.

“We have been through so much during the season with a lot of situations we have overcome and that is the spirit of the team. We have many other tools to achieve what we want and we will give it a go.”