UFC 48: Payback was a mixed martial arts event held by the Ultimate Fighting Championship on June 19, 2004, at the Mandalay Bay Events Center in Paradise, Nevada. The event was broadcast live on pay-per-view in the United States, and was later released on DVD.

The featured contestants of the evening were Ken Shamrock and Kimo Leopoldo, who had met once before in 1996 in a UFC title fight at UFC 8, with Shamrock reigning victorious. The event was very successful, as it drew more pay per view buys than the highly anticipated match between Chuck Liddell and Tito Ortiz one event earlier at UFC 47.

The total fighter payroll for UFC 48 was $586,000.

Ken Shamrock: $170,000 ($120,000 to fight; $50,000 to win)

Matt Hughes: $110,000 ($55,000 to fight; $55,000 to win)

Frank Mir: $90,000 ($60,000 to fight; $30,000 to win)

Kimo Leopoldo: $55,000

Tim Sylvia: $40,000

Evan Tanner: $30,000 ($15,000 to fight; $15,000 to win)

Phil Baroni: $20,000

Frank Trigg: $20,000 ($10,000 to fight; $10,000 to win)

Matt Serra: $16,000 ($8,000 to fight; $8,000 to win)

Kenneth Wayne Shamrock (born Kenneth Wayne Kilpatrick; February 11, 1964) is an American mixed martial artist, UFC Hall of Famer and professional wrestler. Shamrock emerged as one of the biggest stars in the history of mixed martial arts, headlining over 15 main events and co-main events in the Ultimate Fighting Championship and Pride Fighting Championships during the course of his career and set numerous pay per view records with his drawing power. Shamrock is widely considered to be a legendary figure and icon in the sport of mixed martial arts. Shamrock was named The World's Most Dangerous Man by ABC News in a special entitled "The World's Most Dangerous Things" in the early part of his UFC career, a moniker which has become synonymous as his nickname.

Shamrock became known early on in the UFC for his rivalry with Royce Gracie. After fighting to a draw with Gracie in the inaugural Superfight, he became the first UFC Superfight Champion after defeating Dan Severn at UFC 6; the title was eventually renamed the UFC Heavyweight Championship when weight categories were introduced to the UFC. He was also the first foreign MMA Champion in Japan, winning the title of King of Pancrase. During his reign as the UFC Superfight Champion, he was widely considered the #1 mixed martial artist in the world. Shamrock was also ranked by Inside MMA as one of the top 10 greatest mixed martial arts fighters of all time.

Jacob Christopher "Tito" Ortiz (English: /tɪtɵ ɔərtɪs/) (born January 23, 1975) is an American mixed martial artist and former UFC Light Heavyweight Champion, having held the title from April 14, 2000 to September 26, 2003. Along with fighters like Randy Couture and Chuck Liddell, he was one of the sport's early stars. Ortiz ultimately became the biggest pay-per-view draw of 2006 for his fights with Liddell, Forrest Griffin, and Ken Shamrock.

Outside of his fighting career, Ortiz is the CEO of the Punishment Athletics MMA equipment and clothing line. He also owns an MMA training gym called Punishment Training Center, which is located in Huntington Beach, CA.

Jacob Christopher Ortiz was born to Samuel and Joyce Ortiz. He received his nickname "Tito," which means tyrant, from his father when he was a year old. He is the fourth child of his mother, Joyce, who had three sons from a previous marriage. His mixed heritage (Mexican father, American mother) has been reflected in his ring entrances as he has borne both Mexican and American flags.

Kimo Leopoldo (born January 4, 1968), or simply Kimo, is an American mixed martial artist. He made his MMA debut at UFC 3 in 1994 losing to Royce Gracie by submission. Kimo's fighting style has been described as freestyle, with a mixture of striking and grappling techniques.^{[citation needed]}

He was credited with a black belt in Taekwondo in his Ultimate Fighting Championship debut at UFC 3. Kimo is well known for his Christian beliefs: he sports many religious tattoos, and entered the arena at UFC 3 carrying a large cross on his back.

At UFC 3, Kimo fought the reigning, defending UFC 1 and UFC 2 champion Royce Gracie in the quarterfinals. Kimo gave Gracie his toughest fight to date but eventually lost the fight via submission. Gracie was dehydrated following his bout with Kimo and, as a result, Gracie's corner threw in the towel before the start of his next match. This subsequently made Kimo into an enormous star in the martial arts world.

After three straight wins in Japan, including a dominant, impressive win over UFC 2 finalist Pat Smith, Kimo returned at UFC 8 and fought reigning UFC champion Ken Shamrock in a title match for the UFC Superfight Championship, but lost early in the fight via submission due to a kneebar.

Matthew James Lindland (born May 17, 1970) is an American mixed martial artist, Olympic wrestler and politician. He won the Oregon Republican Party's nomination for the Oregon House of Representatives, District 52 seat on May 20, 2008.

Lindland started wrestling at age 15 at Gladstone High School in Gladstone, Oregon. In 1991, he won the junior college 158 lbs national title wrestling for Clackamas Community College.

Lindland then went on to wrestle at the University of Nebraska, Division 1 of the NCAA. He won the Big Eight title at 158 in 1993. Following up that title, Lindland had a record of 36-0 for the 1993 season going into the National Tournament, and was the #1 ranked wrestler for his weight class. He suffered an upset in the first round of the tournament however, and did not place. Following his college career Lindland began to compete in both Freestyle and Greco-Roman events, finding success in both but ultimately deciding to concentrate all his effort upon the Greco-Roman style.