Diego Costa has endured a tough season on and off the field, but the World Cup has seen him show how good he really is in-front of goal.

Despite netting 20 goals in Chelsea's 2016/17 title-winning season, manager Antonio Conte told Costa via text message he was not in the plans for the following campaign.

It was revealed in September 2017 that Costa would return to former club Atletico Madrid the following January, scoring a respectable seven goals in 23 appearances for Los Colchoneros.

He's started the 2018 World Cup in a rich vein of form though, netting twice against Portugal before bagging a somewhat-fortunate goal in a 1-0 win over Iran in Kazan.

Ramin Rezaeian's attempted clearance cannoned off the leg of Costa, before the ball nestled in the back of the net.

Costa never makes many friends on the pitch due to his confrontational style, he's never too shy to cause an argument with an opponent.

One such player that has come up against Costa is Iran centre-back Morteza Pouraliganji, who had the tough job of keeping the 29-year-old quiet, and almost succeeded.

Unfortunately for the world-renowned Spaniard, his mouth has gone running away from him if the Iranian defender is to be believed.

“He looked at me and insulted my mother and my sister,” Pouraliganji said, per the Tehran Times.

“Costa started insulting me after 10 minutes. He wanted to make me angry but I kept my cool."

Very disrespectful if true from Costa, and judging from previous actions it wouldn't be too hard to believe.

To add further fuel to the fire, Pouraliganji was further critical of the Spanish hitman for his performance against the Iranians.

“I don’t know why he was selected as the Man of the Match because he touched the ball just for five times and accidentally scored a goal,” Pouraliganji added.

Extremely salty from the defender, but understandable considering Costa supposedly fired shots at his family.

If only Costa could let his feet write the headlines instead of his mouth for once...