In one corner, Saul "Canelo" Alvarez. In the other, Lionel Messi.
The Argentina star may have gotten into trouble with the wrong person after moving the Mexican national team jersey with his foot while celebrating his team's much-needed World Cup win against Mexico on Saturday.
The Mexican boxer said on Twitter that Messi " was cleaning the floor " with the Mexican shirt. He said it was a disrespectful attitude by the Argentina star toward the Mexicans.
"He better ask God not to run into me," Canelo tweeted.
Messi was taking his right shoe off when he - apparently without intention - moved the Mexico shirt which he had exchanged with a Mexican player after Argentina's 2-0 win. The shirt was on the floor as the Argentines celebrated in the locker room.
Former Argentina forward Sergio "Kun" Aguero came out on Messi's defense.
"Mr. Canelo, don't go finding excuses or creating trouble, certainly you don't know soccer or what happens in a locker room," he said on Twitter. "The shirts are always on the floor after a match as they are sweaty."
Former Spain player Cesc Fabregas also defended Messi, saying it's normal for players to leave the shirts on the floor before they can be taken to be washed.
The 35-year-old Messi is trying to win his first World Cup title with Argentina. The win over Mexico kept the Argentines in position to advance to the knockout round.