Celtic manager Neil Lennon told ITV's Gabriel Clarke he thought Scott Brown's sending off was very harsh.
The Scottish midfielder was dismissed after kicking out at Neymar during the second half.
"No I'm not convinced it is [a red card]. If there's any contact it's minimal. It's changed the game. I can't speak highly enough of the players," Lennon explained.
"He [Neymar] has a reputation in the game, and sometimes he exaggerates things."
Despite going down to ten men, Celtic had chances to win the game, with both James Forrest and Charlie Mulgrew going close.
"We had two good chances just before they scored - Valdes made a great save and Mulgrew should have done better with his header."