Liverpool have drawn three of their opening four Premier League matches, although they began their Champions League campaign with a victory over Atletico Madrid. Iraola admitted that managing player workloads has been one of his main challenges early in the season.
"There are players who play every three days with no issues. They are very robust, their performances don't change too much," Iraola said.
"There are other players where the risk is bigger and the performances are different. I have to learn who is ready to play games every three days and who needs a rest so their performance level isn't affected."
Iraola believes Liverpool's more experienced players have already shown they can cope with the demands, with captain Virgil van Dijk among those he trusts to handle the schedule.
"Virgil can do it, because he has done it before, he has the experience and his performance isn't so affected," he said.
However, the Liverpool boss is taking a more cautious approach with younger players and recent arrivals who are still adapting to English football.
"With the younger ones and those coming from abroad, there are some question marks, for them and for me and everyone. We will have to study it case by case," Iraola said.
One confirmed change will come in goal, with Giorgi Mamardashvili expected to start ahead of first-choice goalkeeper Alisson Becker.
"I rate Giorgi very highly, I know him from Spain. We tried to sign him for Bournemouth before I came here," Iraola said.
"For me, he's a very good keeper and he's going to start tomorrow."
There was also positive news on the injury front, with Joe Gomez back in training and available for selection. Conor Bradley remains sidelined.