It's a rematch five years in the making and with the highest stakes imaginable on the line.

Roger Gracie and Marcus "Buchecha" Almeida will settle things once and for all at Gracie Pro this Sunday in Rio de Janeiro live on FloGrappling. This is a bout many in the Brazilian jiu-jitsu community have deemed to be the greatest matchup of all time and pits two of the biggest names to ever compete in the sport head-to-head. 

Gracie, a grappling legend from the first family of BJJ and MMA, has dabbled inside the cage from time to time, but where he's made an indelible mark has come on jiu-jitsu mats around the globe. During his prime, Gracie notched three Open World Championships, a feat many believed could never be topped --that's until Almeida emerged onto the scene in 2012.

In the past five years, "Buchecha" has carved out his place as the current king of jiu-jitsu by winning four Open World Championships and notching victories over every major name in the sport along the way. That said, the one marquee win he doesn't have on his resume is against Gracie, and the two kings will step in to do battle this Sunday night in a highly anticipated rematch.

With their first meeting ending in a controversial draw, it's only fitting their second clash will come under submission-only rules. That means there will be no draw, just one winner and one loser, once and for all to settle who is the true reigning king of BJJ.

That's drama at its finest and competition at a level unheard of around the grappling world. Tune into FloGrappling on Sunday to check out the action, or pick up a universal subscription to make sure you don't miss any of the best moments from this weekend's wrestling, grappling, and combat events.