Liverpool come into this clash off the back of four wins across their last five matches in all competitions, following a 1-0 win at the Vitality against Bournemouth before the international break.
The Reds welcome Premier League leaders City to Anfield in what will be a frosty atmosphere following the charges brought against the club over the past month.
Isak and Gakpo ruled out
A win for Iraola could help his side jump into the top four after a tricky but unbeaten start to the campaign. Speaking first on injuries, Iraola confirmed news that no Liverpool wanted to hear as Alexander Isak and Cody Gakpo are ruled out.
"Yes, Alex Isak and Gakpo won't play, not ready unfortunately for us. Injuries in the break. You always hope the doctor doesn't call you, but we have been unlucky. They are not going to be involved.
"Timeframe - Gakpo has an ankle injury, a matter of him dealing with the pain. A bad tackle, I think. He is working but not for Sunday.
"Isak has a thigh injury; whenever he feels ready, they don't look like long-term injuries. But they are not ready for Sunday.
"(Lewis) Koumas has our trust, you know. No big surprise. The player has shown he is ready to go. We have other players who can cover the positions, so we take the decision."
He also commented on Jeremy Jacquet's fitness: "He is fit and ready to go. He will be fine; we need to train tomorrow."
Iraola excited for the game ahead
Despite the costly injuries, Iraola is looking forward to the clash against City and believes that the uncertainty of the game will only make it more exciting as Liverpool test their mettle against Enzo Maresca's side.
"I think uncertainty is not good for anyone involved, but the process is ongoing, so we have to be patient," Iraola said.
"It's an exciting game, at home at Anfield against league leaders. Won all their games. They will go for it, so will we; we have to be ready and help our supporters. I hope we are at the level. I think it is still very early, whatever happens on Sunday.
"Just five games, but it is true we like to face teams like City and show our level, definitely. It's massive for everyone involved; it's an exciting moment.
"I think the challenge of the game you want is so high that I don't think the players think too much outside of this; they know they need to be at this high level. They are focused on those things. They will have their own opinions, but they are focused."
Koumas might have to step up
Lastly, as Liverpool prepare to make Anfield a fortress against a relentless City side, Iraola revealed who could replace Isak as the team's main striker. Koumas could step in, as could Bradley Barcola or Federico Chiesa.
On Barcola: "He has played as a left winger and also as a striker, so he can cover three positions up front."
On who could replace Isak: "Even before we don't have Hugo Ekitike, who I am looking forward to having available. Maybe we will recover Chiesa, but he hasn't played any minutes. As a number nine, we only have Koumas right now; we have some options: wingers who have played up front.
"We don't have a lot of time to train with the group as a whole. It is the same for every team, so we cannot use it. I had time to watch and analyse, but we have to adapt to injuries. Alex, and then Cody and now this is City, then Champions League, so the run of games, we have to get used to these things."