Olivier Giroud feels Marc-Andre ter Stegen's superb save to keep out his header just seconds before Lionel Messi's opening goal could define Arsenal's Champions League tie with Barcelona.
Barcelona goalkeeper Ter Stegen got down low to his right to deny Arsenal striker Giroud with 20 minutes remaining of the round-of-16 first leg at Emirates Stadium on Tuesday.
In less than a minute, reigning champions Barca were a goal to the good after a ruthlessly efficient counter-attack involving Andres Iniesta, Luis Suarez and Neymar was finished expertly by Messi.
The Argentina star added a second from the penalty spot to put Barca in command ahead of the second leg at Camp Nou on March 16.
Giroud told Arsenal Player: "It's possibly the turning point. I had a duel with the defender and I think that I headed the ball well but the keeper did very well.
"We were not cautious enough of their counter-attack, which is a model counter-attack, and then they finished it well. We couldn't score in the first half after we played well on the counter-attack and were dangerous.
"We couldn't finish our hard work and it's disappointing because at the end of the day we're 2-0 down and our chances of qualifying are very small. There's a lot of disappointment.
"I said before the game that we needed to be cautious if we could not win the game and not concede goals to keep our chances high for the second leg.
"In Barcelona it is very, very difficult to win, so we can have regrets after [the first leg] because we didn't finish our counter-attacks."