One of the most decorated wrestlers to ever compete in MMA, Warren has amassed a slew of achievements across the different styles, Folkstyle, Freestyle and most notably, Greco-Roman. 

Beginning his journey with Folkstyle at East Kentwood Highschool, he would become a 3-time state placer, with 1 state championship in his senior year. Following Highschool he would then wrestle for The University of Michigan, achieving a 3rd place finish at the 2000 NCAA finals. He also achieved a runner up finish at the 1998/99 Big-Ten Conference tournament. 

 
Still hungry for competition, he switched to Greco-Roman fulltime from Folkstyle/Freestyle, embarking on a run that would see him accomplish great success on the highest level, and against the toughest international competitors. His top results include 1st place at the 2006 World Greco Championships, 1st place at the 2007 World Cup,  1st place at the 2007 Pan-American Championship, and three 1st places finishes at the  United States Greco Championships, years 2004 - 2007.  He also scored a 3rd place finish at the senior national Greco Championship in 2003.

 
Among his other achievements in elite-level Greco-Roman events are ; four top-3 finishes at the 'Dave Schultz Memorial International' tournament,  three top-3 finishes at the 'Henri Daglane Challenge' tournament, two top-3 finishes at the 'Sunkist Kids/ASU International', and four top-3 finishes at various 'NYAC International Open' tournaments, and 2004 USA Olympic team trials runner up.

 
He was also a USA World team trials champion in 2005 - 2007, 1st place at the USA-University Greco Championships in 1998, was USA Greco-Roman athlete of the year in 2006, and in 2009 was an inductee in the "Alan and Gloria Rice Greco-Roman Hall of Champions", as part of the "National Wrestling Hall of Fame Dan Gable Museum"


At the 2006 World Greco Championships, Warren defeated a 'murderer's row' of opponents and multiple time World Championship medalists including Dilshod Aripov of Uzbekistan in the opener, ( 2 - 3, 3 - 1, 3 - 1,), Ali Ashkani of Iran in the round of 16 ( 2 - 1, 1 - 1 ), Vyacheslav Djaste of Russia in the quarter's ( 4 - 1, 2 - 1 ), Euseibiu Diaconu of Romania in the semi's ( 1 - 1, 2 - 1 ), and finally David Bedinadze of Georgia ( 1 - 1, 4 - 1, 2 - 1 ), to be crowned the World Champion. 

 
He missed the 2007 Pan-American Championship, as he was penalised for testing positive for cannabis.  In 2008 he was handed an absurd ban of 2 years for the offense, missing the 2008 Beijing Olympics, of which he was the favorite to capture gold. Shortly after this time, Warren decided to transition to MMA, linking up with fellow Greco and MMA veterans at 'Team Quest', to begin his journey.

Making his pro-debut in the '2009 Dream Featherweight Grand Prix', defeating Chase Beebe in the opening round, he would then achieve a huge underdog victory over 17 - 1, acclaimed fan-favorite Norifumi "KID" Yamamoto in the second round, in only his 2nd pro MMA bout. Despite his incredible early success he would succumb to Jiu-Jitsu ace and Hall of Famer Bibiano Fernandes by armbar in the Grand Prix final. After this GP, he went on to sign with Bellator, becoming one of the promotion's pioneers.