“I had asked for Messi's shirt before the game, it's an honour to have it," Insigne told Sky Sport Italia.
“This result leaves a bitter taste, because we played on level terms, showed sacrifice, now we have to think about Serie A and keep doing well."
Sergio Busquets and Arturo Vidal will be suspended for the second leg at Camp Nou on March 18.
“They have other strong players. We have to focus on going there, playing a great game, running some more risks and qualify for the next round.
“It was emotional to take on Barcelona and Messi for the first time, I just feel we could've had a better result in front of our fans, especially with the chances we had."