Jens Johnnie Pulver is an American retired professional mixed martial artist and undefeated boxer and kickboxer. Pulver was the inaugural UFC Lightweight Champion in addition to serving as the head coach on The Ultimate Fighter 5 reality show against long-time rival B.J. Penn. In mixed martial arts, Pulver competed at the Lightweight, Featherweight, Bantamweight and Flyweight divisions in addition to competing at the Middleweight, Light Middleweight, and Welterweight divisions as a professional boxer. While perhaps best known for competing in the UFC, Pulver has also competed in Pride Fighting Championships, for the PRIDE 2005 Lightweight Grand Prix. He is to-date the youngest UFC Lightweight Champion in the UFC history, eventually relinquishing his title, after two defenses, due to a contract dispute. Pulver officially retired from combat sports in 2014.

The Ultimate Fighter 5 was the fifth season of the Ultimate Fighting Championship produced reality television series The Ultimate Fighter. As with the show's usual format, sixteen prospective mixed martial arts fighters were secluded in a house near Las Vegas, Nevada and trained together while participating in a single-elimination tournament, with the winner being awarded a six-figure UFC contract. This season featured only one weight class, lightweights (146–155 lb) and the fighters were divided into two teams; one coached by former UFC Lightweight Champion Jens Pulver and the other by former UFC Welterweight Champion and former lightweight champion B.J. Penn. The season was well-known among fans for the large number of fighters kicked off of the show.