Liverpool goalkeeper Adrian said it was "really difficult" to stay on the line during penalties after his heroics in a UEFA Super Cup win over Chelsea.
Adrian saved the only spot-kick of the shoot-out, denying Tammy Abraham as Liverpool claimed a 5-4 victory after the clash in Istanbul finished locked at 2-2 on Wednesday.
However, the Spaniard appeared to be off his line when Abraham took his penalty, although no retake was ordered, giving the Champions League holders their win.
Adrian, who only signed with Liverpool on August 5 and was making his starting debut, said the rule was tough on goalkeepers.
"It is really difficult to be on the line because we need a step forward to push but in the end we need to wait until he strikes," he told reporters.
"I knew his [Abraham's] strong side is my left, so I tried to go there and save with my right foot."
Sadio Mane's brace had given Liverpool the lead in extra time before Jorginho's penalty forced a shoot-out, only for Adrian to step up.
The former West Ham goalkeeper said he wanted to prove himself with star shot-stopper Alisson out injured.
"It is great to get a title, it is magnificent, to win in this way obviously I am more than double happy," Adrian said.
"I am really proud of all my team-mates and all the fans who came to support us.
"Also, for myself it wasn't an easy debut at Anfield on Friday [against Norwich City] because Alisson had an injury and you know the goalkeeper's life is like this.
"We need to be ready for everything, so I came to show that I have a great level and tonight was a great moment at the end saving that penalty."
Liverpool are back in action with a trip to Southampton in the Premier League on Saturday.