21 of the biggest rivalries in MMA history [UPDATED]

AJ McKee and the Pitbull brothers

It was a rivalry no one really saw coming. But then it was the biggest thing Bellator MMA had ever seen.

When the Bellator Featherweight World Grand Prix came to a close in July 2021 it was just the reigning champion Patricio Pitbull and AJ McKee across the cage from one another. It look McKee just under two minutes to submit Patricio and win the tournament and the title.

Just one fight later Patricio faced McKee again, and this time it was Patricio who won.

But the build up between the first and second fights got violent with both teams storming at the other during public media appearances and had to be pulled apart multiple times.

Then McKee turned his engery to Patricio's brother Patricky, who he felt was "running" from him. McKee even went up in weight with the hopes of earning a shot at the then-lightweight champion. Unfortunately Patricky lost the tile before McKee could fight him.

Now the pair is scheduled in the first round of the Bellator Lightweight Grand Prix where he'll face Patricky on his way to securing another Grand Prix title.