After his successful amateur wrestling career at Bismarck State College and the University of Minnesota ( 106 wins and 5 losses ) , Lesnar signed with WWE ( then the World Wrestling Federation ) in 2000 . He was assigned to its developmental promotion Ohio Valley Wrestling ( OVW ) , where he was a three @-@ time OVW Southern Tag Team Champion with Shelton Benjamin . After debuting on WWE 's main roster in 2002 , he won the WWE Championship on three separate occasions with victories over The Rock and Kurt Angle ( twice ) . Lesnar won his first WWE Undisputed Championship five months after his main roster debut at the age of 25 , becoming the youngest champion in the title 's history . He was also the 2002 King of the Ring and the 2003 Royal Rumble winner , making him the youngest King of the Ring and Royal Rumble winner as well . Following his match with Goldberg at WrestleMania XX , Lesnar left the WWE and pursued a career in the National Football League ( NFL ) . He was named a defensive tackle for the Minnesota Vikings but was cut prior to the start of the 2004 – 05 season . In 2005 , Lesnar returned to professional wrestling and signed with New Japan Pro Wrestling ( NJPW ) , where he won the IWGP Heavyweight Championship in his first match . After a contractual dispute with NJPW , he also wrestled as IWGP Heavyweight Champion in the Inoki Genome Federation ( IGF ) .