Derrick Mehmen has 10 losses against 10 opponents on his MMA record. For a list of Mehmen's best fights, refer to "Best fights of Derrick Mehmen".
On October 6, 2017 Derrick Mehmen faced off against Mikhail Mokhnatkin in a heavyweight bout at age 32. He was coming in with a record of 19-10 (13), and Mokhnatkin was 27 years old and with a record of 9-2-2 (7). Mehmen lost the fight via 3-round unanimous decision.
On April 28, 2017 Derrick Mehmen faced off against Alexei Kudin in a heavyweight bout at age 31. He was coming in with a record of 19-9 (13). Mehmen lost the fight via 3-round split decision.
On August 5, 2016 Derrick Mehmen faced off against D.J. Linderman in a heavyweight bout at age 31. He was coming in with a record of 19-8 (13). Mehmen lost the fight via 3-round unanimous decision.
On October 17, 2015 Derrick Mehmen fought Blagoy Ivanov in a heavyweight title fight for Ivanov's WSOF Championship title. Mehmen was 30 years old and with a record of 19-7 (13), and Ivanov was 29 years old and with a record of 12-1 (9). Mehmen lost the fight via 2nd-round TKO.
On October 11, 2014 Derrick Mehmen fought Smealinho Rama in a heavyweight title fight for Rama's WSOF Championship title. Mehmen was 29 years old and with a record of 18-6 (13). Mehmen lost the fight via 1st-round TKO.
On May 19, 2012 Derrick Mehmen faced off against Gian Villante at age 26. He was coming in with a record of 12-5 (10), and Villante was 26 years old and with a record of 9-3 (8). Mehmen lost the fight via 3-round unanimous decision.
On March 31, 2012 Derrick Mehmen faced off against Rodney Wallace at age 26. He was coming in with a record of 12-4 (10), and Wallace was 30 years old and with a record of 11-4 (3). Mehmen lost the fight via 3-round unanimous decision.
On January 22, 2011 Derrick Mehmen faced off against Gareth Joseph at age 25. He was coming in with a record of 10-3 (10). Mehmen lost the fight via 3-round split decision.
On April 22, 2010 Derrick Mehmen faced off against David Branch at age 24. He was coming in with a record of 8-2 (8), and Branch was 28 years old and with a record of 5-0 (5). Mehmen lost the fight via 2nd-round submission.
On December 11, 2008 Derrick Mehmen faced off against Mike Ciesnolevicz at age 23. He was coming in with a record of 4-1 (4). Mehmen lost the fight via 1st-round submission.