Jeremy Mathew Wariner (born January 31, 1984, in Arlington, Texas) is an American track athlete specializing in the 400 meters. He has won four Olympic medals (three gold, one silver) and six World Championships medals. He is the third fastest competitor in the history of the 400 m event with a personal best of 43.45 seconds. The second fastest is Butch Reynolds and the fastest is Michael Johnson.

A successful college athlete, Wariner won the 400 m and 4 × 400 meters relay gold medals at his first Olympics in Athens 2004. He followed this with two gold medals at the 2005 World Championships in the same events. He remained undefeated in the 400 m event during the 2006 ÅF Golden League, earning him the $250,000 jackpot. He remained World Champion in the 400 meters individual and relay events at the 2007 Osaka World Championships, earning him the 2007 Best Male Track Athlete ESPY Award. He won the 4x400 m relay gold medal at the 2008 Beijing Olympics but took silver in the 400 m, finishing behind fellow countryman LaShawn Merritt. Wariner picked up the silver medal in the 2009 World Championships, again finishing second to Merritt.

Early career 
Jeremy Wariner attended Lamar High School in Arlington, Texas, participating in multiple sports and being recognized for his outstanding speed. Under the coaching of Mike Nelson, who also coached 110 meters hurdler Reggie Harrell at Lamar High School, he was the 2002 Texas 5A state sprint champion at both 200 meters and 400 meters, setting high school bests of 20.41 seconds (wind assisted) and 45.57 s respectively. Enrolling at Baylor University, he quickly established himself as a collegiate sprint talent under the guidance of Clyde Hart, who was also coach of Baylor alumnus and four-time Olympic 400 m gold medal winner and two-time world champion Michael Johnson. Somewhat hampered by injuries late in his freshman year, Wariner regained form as a sophomore, winning both the 2004 NCAA Division I indoor and outdoor 400 m titles. Later that year, he claimed the national 400 m title at the USATF Championships making him the favorite for the gold medal at the 2004 Summer Olympics inAthens.

Wariner then made his first appearance on the world athletic stage at the 2004 Summer Olympics. He won two Olympic gold medals, the first in the 400 m in a personal record 44.00 s and the second as the third leg of the U.S. 4 × 400 meters relay team. Following his Olympic successes, he turned professional, forgoing the rest of his collegiate eligibility, though he remained at his mother's & father's house and continued to be coached by Clyde Hart.

Professional career
The next year, Wariner won the 400 m at the 2005 USATF championship with a time of 44.20 s. At the Helsinki World Championships on a cold and rainy day he won the 400 m in 43.93 seconds. He would then anchor the American team in the 4 × 400 m relay for the gold medal.

Early in 2006, Wariner competed in the 200 m lowering his personal best to 20.19 s. Later that year he would set a new personal best of 43.62 seconds at 400 m at the Golden Gala Meet in Rome. Together with Asafa Powell (100 m) and Sanya Richards (women's 400 m) he won his sixth out of six Golden League events (400 m) in the same season, which earned him a total of $250,000.

In 2007 he filled a summer with dominating 400 m performances culminating with the Osaka World Championships where on August 31, 2007 he would win the 400 m in 43.45 s thereby improving his personal best to become the third-fastest of all time (only Michael Johnson and Butch Reynolds have run faster).

Rivalry with Merritt
In 2008, Wariner left long-time coach Clyde Hart in favour of working with Baylor assistant coach Michael Ford. This was an unexpected move as Wariner had much success under Hart, who had also coached his agent Michael Johnson. Wariner stated that he needed a change as Hart was nearing retirement, although the coach said that the split was due to a pay dispute. By the time of the 2008USATF championship Wariner and Johnson had to face many probing questions regarding the reasons for such a change in an Olympic year. He finished second to LaShawn Merritt in the 400 m final of theUSATF championship and secured his place on the U.S. Olympic team in the 400 m event and the 4x400 m relay team.

In the 2008 Olympics, Wariner qualified for the final with a time of 44.12 s, in a run which he slowed down considerably in the final fifty meters. This led to much anticipation that he could beat Michael Johnson's world record in the final, but instead he took the silver, unexpectedly losing to LaShawn Merritt by nearly a full second. David Neville came in third completing a United States sweep of the 400 m.

Following his disappointment with the silver medal at the Olympics, Wariner admitted he had made a mistake in sacking Hart. He apologized to the emeritus coach after Johnson advised him that his new workout programme with Ford was lacking in some areas and took him back on as Coach. The emergence of Merritt had left Wariner as the second-best athlete for the first time in his professional career.

In the 2009 World Championships, Wariner won the silver medal in the 400 m, again finishing behind LaShawn Merritt, and the gold medal in the 4x400m relay.

2012 London Olympics 
Wariner was named to his third Olympic team as part of the Team USA 4x400m relay squad. The two-time Olympic medalist in the 400m had failed to make the individual 400m event after starting poorly and finishing sixth in 45.24 seconds in the US Olympic Trials in Eugene, Oregon on June 24, 2012. At the Olympics, his rival LaShawn Merritt did not finish his qualifying heat in the 400m due to injury, and could not run the 4×400m relay. Wariner pulled out of the Olympics due to a torn hamstring.

2013 Victorious Comeback 
In March 2013, Wariner returned to the ways of glorious victory by becoming the National Champion at 400 m at the USA Indoor Track & Field Championships.

Personal bests