The Liverpool manager will face the Villarreal manager at Anfield on Tuesday, with their professional relationship stretching back to their playing days together at Athletic Club in Bilbao.
Iraola and Pérez have remained close since their time at Athletic, where they progressed from the academy into the first team. After Pérez retired, Iraola brought him into his coaching staff at Rayo Vallecano in 2022, before attempting to reunite with him at Bournemouth the following year.
“For me it’s a special game because Iñigo is my friend,” Iraola said. “We’ve known each other since the academy years at Athletic Club, we played with each other in the first team, and as soon as he retired I was quick enough to grab him to help me as an assistant.
“We’ve been through a lot of things together, so it is also a privilege for me to face him in a Champions League game.
“He knows me very well, he knows everything, but also it is a team I follow, I know the players and it is going to be little bit strange, yes, but in a good way.”
Their familiarity has made the build-up unusual. Iraola explained that they normally speak regularly about football, family and life, but have kept their distance as the meeting approaches.
“I talk to him a lot, but when you know you are going to face each other you stop talking because you kind of leave some distance,” he said. “We normally call time to time to talk about La Liga, the Premier League, about football, about other stuff, our families, but now when the game gets closer we haven’t been in touch.”
Iraola tried to bring Pérez to England when he took charge at Bournemouth, but the move fell through after a work permit application was rejected. The Spaniard said he challenged the decision, believing his proposed assistant should have been allowed to take the role.
“He wanted to work here for us at Bournemouth, but if you don’t have the work permit you cannot do anything,” Iraola explained. “You cannot put the kids in a school. There was a moment when we realised it was not going to be possible.”
Pérez instead took charge of Rayo Vallecano, building his own managerial career and eventually earning the chance to lead Villarreal into the Champions League. Iraola said he was pleased with how events unfolded for his friend, while also crediting Tommy Elphick and Shaun Cooper for taking on greater responsibility at Bournemouth.
The Liverpool boss also reflected on his own final goal as an Athletic player, scored in a 4-0 home win in May 2015.
“Last game in San Mamés for me, very special. I think I had one of the best last days you can ask for. We qualified for Europe in that game. I scored, we won 4-0 and everyone was happy.”
Now, with their careers taking them to opposing dugouts on one of European football’s biggest stages, the friendship will briefly give way to competition.