Cristiano Ronaldo's double was overshadowed by Costa's shocking antics at Allianz Stadium, as the former Bayern Munich man was dismissed in the closing stages for spitting at Federico Di Francesco, having already elbowed and head-butted his opponent.

Costa looks set for a minimum three-match suspension and Allegri, who believes that the Brazilian fell for provocation, revealed that a club fine will also be issued.

"It's only right that he is fined, and he certainly will be," Allegri said. "I was surprised by his reaction. We have suffered a goal, a red card and a suspension which will be long."