Barcola, 24, was handed his first Liverpool start since joining from PSG for a reported £123 million, including add-ons, this summer.
The winger’s night was cut short, however, as he was forced off in the 60th minute with that appeared to be a calf injury.
He pulled up while running through on goal and fell to the turf holding his calf. Following treatment from the Liverpool medical staff, he was replaced by Victor Munoz.
Speaking to TNT Sports after the game, Iraola made sure to ease any anxieties, confirming that Barcola’s issue was just cramp.
"No, just cramps, especially with Bradley,” he said.
"We are kind of rushing him a little bit. We wanted him there, but at the end we decided to say give us what you have then that's the most he has. Let's see how they recover for the next one."
On the crowd: "I was enjoying it. They're a very good team. Technically, in the middle, lovely players. It is not easy to press those players as they have quality.
"They have been playing together forever. We find another comeback after Forest, after Newcastle. We still have this thing to improve in the beginning of the games, but I am happy as we have shown some character.
"This is the Champions League, you don't have easy games."