The contest was heavily promoted, featuring a publicity tour to Canada and Hawaii, as well as the introduction of UFC Primetime, a preview show that cost $1.7 million to produce.

The co-main event of the evening was a battle between two undefeated light heavyweights sporting 13–0 records in Lyoto Machida and Thiago Silva.

"[4] The fans voiced their opinion in a poll conducted by Inside MMA, where 45 percent of the viewers voted the match up between St-Pierre and Penn as the most anticipated fight to take place between December and February.

The poll also featured (in descending order according to the results) Fedor Emelianenko vs. Andrei Arlovski, Wanderlei Silva vs. Quinton Jackson, and Rich Franklin vs. Dan Henderson.

[8] Promotion for the St-Pierre and Penn contest began in November 2008, with UFC President Dana White, and the two main event fighters embarking on publicity tours in Toronto, Ontario, Canada and Honolulu, Hawaii.

[19] Penn made a subsequent appearance on TapouT radio to discuss this report and confirmed that he has taken issue with his portrayal on the show.

[22] The co-main event featured a bout between two top contenders and undefeated light heavyweights, Lyoto Machida and Thiago Silva.

[24] Machida is a fighter who prefers to counter-strike,[25] and combines Shotokan Karate, sumo wrestling and Brazilian jiu-jitsu to form his own style.

[30] Bonnar, a light heavyweight, was to take on Matt Hamill at UFC Fight Night 13, but a left knee injury during training forced him out of that bout.

His opponent, the 21-year-old Jon Jones was a national amateur wrestling champion and coming off a unanimous decision victory over Andre Gusmão at UFC 87, where he took the fight on three weeks notice.

[31] Rounding out the main card was a lightweight contest between the winner of the fifth season of the UFC's reality television series and MMA competition The Ultimate Fighter, Nate Diaz, and contender Clay Guida.

Diaz is a Brazilian jiu-jitsu brown belt under Cesar Gracie, and Guida is noted by MMA journalist Sam Caplan as one of the UFC's most highly regarded fighters.

[38] O'Brien, a former wrestler at Purdue University, was able to take Wellisch down and control his opponent on the ground but was hurt on the feet in the first and second rounds.

[37][38] In one of the two bouts being awarded "Fight of the Night" bonuses, John Howard defeated Chris Wilson by split decision in their welterweight contest.

[39] Fitch came close to submitting Gono in the first and second rounds when he went for a rear naked choke and an armbar respectively, but he was unable to finish the Japanese fighter.

[40] After closing the distance, Guida used his wrestling experience to avoid submissions while controlling and pressuring Diaz both in the clinch and on the ground throughout the fight.

[36] The second bout saw two judo black belts fighting as Karo Parisyan went up against undefeated Dong Hyun Kim in a matchup at welterweight.

[41] The fourth fight featured two undefeated Brazilians meeting at light heavyweight in Lyoto Machida and Thiago Silva.

[37][44] Round two started with two fighters throwing strikes with St-Pierre landing a punch drawing blood from Penn's nose.

There Penn attempted to defend using the rubber guard, but St-Pierre passed to half-guard and eventually side-control while landing punches.

Vaseline is used to aid cuts in boxing as well as MMA, but applying it to parts of the body other than the face is illegal because of the element of grappling in the sport.

In addition, Penn's head coach, Rudy Valentino alleged that St-Pierre also had an illegal substance on his body during his April 2008 rematch with Matt Serra.

Penn filed a formal request for investigation to the NSAC stating that St-Pierre used an illegal "greasing" agent on his body during the fight.

It continued by accounting an apparent "pre-bout warning" made by Penn's camp to the NSAC that St-Pierre will engage in the illegal application of vaseline.

[52] Georges St-Pierre spoke to Sports Illustrated with regard to the controversy stating, "I haven't seen the fight yet, but I remember at some point something happened and the athletic commission was complaining.

[58] Following the main event at UFC 94, top welterweight contender Thiago Alves made his way into the cage to congratulate St-Pierre on the victory.

[60] St-Pierre's dominant victory also opened up discussion for a possible "superfight" with UFC Middleweight Champion Anderson Silva in 2010.

Instead, a scheduled fight between former UFC Light Heavyweight Champion Quinton Jackson and Keith Jardine would determine Machida's title fate.

A victory for Jackson would earn him a fight with champion Rashad Evans, but a win for Jardine would mean Machida will be awarded with a title shot.

Following the loss to Machida, Thiago Silva was scheduled to return to action against former champion Forrest Griffin at UFC 101,[66] but his opponent was later changed to Keith Jardine.