Big Nog first battled Fedor on Mar. 16, 2003 at Pride 25. He would lose that fight, and the Pride Heavyweight Championship, in a hard fought decision.
While Fedor had gone the distance before, Nogueira was the first fighter to pose a real challenge to "The Last Emperor."
The two would not fight again for over a year, in which time Fedor would continue to finish his opposition while Big Nog would string together five-straight wins to include capturing the interim-Pride Heavyweight Championship after submitting Mirko Cro Cop (who Fedor was rumored to be dodging at the time).
Their rematch would take place on Aug. 15, 2004 in the finals of the 2004 Heavyweight Grand Prix at Pride Final Conflict 2004 to determine the undisputed Pride heavyweight king.
Unfortunately this fight would end in a no-contest due to an "accidental" headbutt, which opened a deep cut over Fedor's eye. Some were quick to blame Fedor, as Big Nog was getting the best of him prior to this.
Their third match would be each fighters next outing in order to finally finish the Heavyweight GP, and unify the Pride Heavyweight Championship. This bout took place on New Years Eve of that same year, and would once again end in hard-fought decision win for Fedor.
While Big Nog was never able to get the "W" over Fedor, these epic battle were the most intense heavyweight fights taking place at that time in the world.