The attacker netted twice for his side as they twice came from behind to win the ill-tempered game and make it 4-2 on aggregate as they progressed to the last four of the tournament.
Gabi, who was one of two Atleti players dismissed during the game, branded the Brazilian "irritating" because of his tendency to wind opponents up and he suffered the wrath of fans at the Vicente Calderon, who jeered him.
The youngster has since taken to social media to slam those responsible.
"No one is obliged to like anyone, but there is a thing called respect," he wrote on his Instagram account.
The 22-year-old has scored 21 goals in 25 games in all competitions for Barcelona this season.
