The AC Milan CEO has claimed that he has seen few goals better than the Argentine's opener against his side on Tuesday
The Argentine opened the scoring against the Italians with a fantastic strike from outside the area as the Blaugrana emerged 4-0 victors, leaving the 68-year-old lost for words.
"It was something of great beauty, certainly one of the most beautiful things I have seen in 60 years of football. We could only bow and applaud," he told the Corriere dello Sport.
Despite his admiration for Messi's strike, Galliani was disappointed with his side's performance in Spain, particularly on the defensive front.
"The strangest thing about the game at Camp Nou was the danger we were creating in possession, yet out of possession we did not look ourselves and every time we lost the ball we nearly conceded a goal," he added.
"Moreover, even on dead-ball situations we were not as clever as we are usually, which lead to the fourth goal."