Jeff Monson is a light-heavyweight fighter who fought for most of his career at heavyweight. He is known for his tendency to attempt anaconda chokes during fights.
In August of 2010, Monson fought Jason Guida and defeated him via rear-naked choke in the second round. He extended his win streak to three consecutive victories with another win over a late replacement for Neil Wain, Dave Keeley. He won the fight via submission due to his specialty, the anaconda choke.
He next fought Travis Fulton in Florida defeating him via first-round kimura submission. He next faced Sergey Shemetov in Israel, fighting for the eighth time in the year of 2010. He dominated Shemetov on the ground with knees from side control and finished him via first-round kimura submission.
He then faced Maro Perak, winning the SHC heavyweight title with a unanimous decision victory.
Monson next made his Strikeforce debut replacing an injured Shane Del Rosario against undefeated Olympic wrestling veteran Dan Cormier. Cormier defeated Monson via dominant unanimous decision. After the fight, Monson dropped down to light-heavyweight.
Monson next faced newcomer Paul Taylor (not the welterweight Paul Taylor), defeating him via first round rear-naked choke submission.
He moved back UP to heavyweight for the opportunity to make his M-1 Global debut against former Pride heavyweight champion, the legend Fedor Emelianenko. The fight was considered to be one of the worst of 2011, but Emelianenko took home a unanimous decision victory. Some angry fans speculated that the fight was rigged but Monson reported that he suffered a broken leg from Emelianenko's kicks during the bout.
After recovering, Monson signed on to return to M-1 to face Bellator veteran Alexey Oleinik. Monson defeated Oleinik via unanimous decision.
Monson then faced Chaban Ka, fighting to a draw after fifteen minutes. Monson went on to fight Jim York in Sydney, Australia and win via unanimous decision. He then returned to M-1 to face Denis Komkin, winning very easily in the first round with his signature north-south choke submission.
Monson then fought in M-1 again defeating Fedor's brother Aleksander Emelianenko via an impressive second-round north-south choke submission.
Monson next fought Drazen Forgac defending his SHC Heavyweight Championship. He defeated Forgac via second round technical knockout after Forgac tore his ACL fifty-eight seconds in.
Monson next returned to M-1 losing to Magomed Malikov via second round doctor stoppage technical knockout.
Monson then fought Alexey Oleinik losing via second round rear-naked choke submission.
Monson then fought Satoshi Ishii losing a unanimous decision.
Monson was next set to fight Vinny Magalhaes but he was forced to pull out of the fight due to a prolonged back injury.
Monson next signed to fight Bellator veteran Mike Hayes losing via a third round headkick knockout for his third straight loss.
Monson next fought Shakhmaral Dzhepisov in Kazakhstan losing via a vicious third round knockout due to punches for his fifth straight loss. Fans and analysts began calling for Monson's retirement but it seemed unlikely.
- Chuck Liddell vs. Jeff Monson - The fight was middleweight which was later renamed to light-heavyweight (205 lbs.) The fight was Monson's "middleweight" debut. Chuck Liddell brutalized Monson's left leg with leg kicks in the last two rounds, while defending takedowns.
- Ricco Rodriguez vs. Jeff Monson 1
- Jeff Monson vs. Branden Lee Hinkle
- Pedro Rizzo vs. Jeff Monson 1
- Josh Barnett vs. Jeff Monson - The fight was Monson's Sengoku debut and his only fight thus far for the promotion.
- Roy Nelson vs. Jeff Monson - The decision which declared Monson as the winner of the fight is widely thought to be controversial. Many thought Roy Nelson won the fight.
- Sergei Kharitonov vs. Jeff Monson - The fight was the first time that Sergei Kharitonov had been submitted in his career.
- Pedro Rizzo vs. Jeff Monson 2 - Monson was on a big win streak coming into this fight, and Pedro Rizzo was on a slight knockout losing streak.
- Jeff Monson vs. Travis Wiuff
- Jeff Monson vs. Travis Fulton
- Jeff Monson vs. Tony Lopez
- Daniel Cormier vs. Jeff Monson - Jeff Monson was a replacement for an injured Shane Del Rosario.
- Fedor Emelianenko vs. Jeff Monson - Some fans suspected that the fight had been rigged in the favor of Fedor Emelianenko, based on Monson's fight behavior.
- Jeff Monson vs. Denis Komkin - The fight was in the M-1 Global promotion.