Brock Lesnar has three losses against three opponents on his MMA record. For a list of Lesnar's best fights, refer to "Best fights of Brock Lesnar".
On December 30, 2011 Brock Lesnar faced off against Alistair Overeem in a heavyweight bout at age 34. He was coming in with a record of 5-3 (4), and Overeem was 31 years old and with a record of 35-11 (33). Lesnar lost the fight via 1st-round TKO.
On October 23, 2010 Brock Lesnar met Cain Velasquez in a heavyweight (UFC Championship) title defense fight. Lesnar was 33 years old and with a record of 5-2 (4), and Velasquez was 28 years old and with a record of 8-0 (7). Lesnar lost the fight via 1st-round TKO and lost the title.
On February 2, 2008 Brock Lesnar faced off against Frank Mir at age 30. He was coming in with a record of 1-1 (1), and Mir was 28 years old and with a record of 10-3 (6). Lesnar lost the fight via 1st-round submission.
