When Michael Phelps won his record-setting 19th medal Tuesday night by anchoring the victorious U.S. men's 200-meter freestyle relay team, he earned the title of most decorated Olympic athlete in history.
Still up for debate, however, is whether having the most medals also makes him the greatest Olympian ever.
[Photos: Michael Phelps and his 19 medals]
Past Olympic greats can't match Phelps' 15 gold medals or his record eight finishes atop the podium at a single Olympics, but that's often no fault of their own. A dominant swimmer has many more chances to medal than top athletes in sports with fewer disciplines or even the stars of track and field who cannot compete in more than a few events because of the difference in distances.
Is British rower Steve Redgrave not as successful an Olympian as Phelps because he only won six medals? He won gold in five consecutive Olympic Games between 1984 and 2000.
What about U.S. track and field star Carl Lewis? He finished first in the long jump at four straight Olympics and also won a total of five other golds and one silver in the 100 meters, 200 meters and 4x100-meter relay.
[Related: Michael Phelps sets record with 19th medal]
And are any of those accomplishments any less significant than what Jesse Owens achieved in 1936? He singlehandedly disproved Hitler's "master race" theory on German soil by famously winning four gold medals in the 100 meters, 200 meters, 4x100-meter relay and the long jump.
In reality, any attempt to rate history's greatest Summer Olympians is not going to be an exact science because of the apples-and-oranges comparisons among sports, eras and genders. My attempt to determine where Phelps belongs is below, and I expect plenty of disagreement.
1. Carl Lewis, USA, Track and Field
Medals: 10 (9 gold, 1 silver)
The most amazing aspect of Lewis' track and field dominance is the longevity he enjoyed in events in which success is typically fleeting. In 1984, Lewis matched Jesse Owens' 1936 performance by winning gold in the 100, 200, 4x100-meter relay and the long jump. He went on to capture five more golds and a silver in the next three Olympics, setting two world records in the 100 meters and going seven years without a loss in the long jump in the process.
2. Michael Phelps, USA, Swimming
Medals: 19 (15 gold, 2 silver, 2 bronze)
Under enormous pressure to become the first athlete ever to capture eight golds in a single Olympics in 2008, Phelps thrived in the spotlight. He won all eight races he entered, the crowning achievement in an unparalleled swimming career. It's fair to note Phelps has had a smorgasbord of chances to win medals, but he has also won gold in multiple disciplines, from butterfly to freestyle to individual medley. Of the 21 finals he has made so far, he has won medals in all but two.
3. Larisa Latynina, Soviet Union, Gymnastics
Medals: 18 (9 gold, 5 silver, 4 bronze)
In a sport in which it's rare for an athlete to have success in more than one Olympics, Latynina dominated three. She established the Soviet Union as the premier gymnastics power in the world, leading her country to team gold at the 1956, 1960 and 1964 Games and taking two golds and a silver in the all-around competition during that time period. Latynina's 18 medals were an Olympic record until Phelps surpassed her on Tuesday.
4. Mark Spitz, USA, Swimming
Medals: 11 (9 gold, 1 silver, 1 bronze)
With a mustache for the ages and a competitive streak to match, Spitz won gold medals at the 1972 Munich Games and set world records in each event. It was the best performance from any athlete at a single Olympics until Phelps surpassed him in 2008. Spitz might be higher on this list had he not retired at age 22 immediately after the Munich Games. He briefly came out of retirement in 1992 to attempt to make the Olympics at age 41 but fell two seconds short in the butterfly.
5. Jesse Owens, USA, Track and Field
Medals: 4 (4 gold)
If Owens' four gold medals in Munich don't make him the greatest Olympian in history, they certainly make him the most significant. Owens dismantled Hitler's Aryan race propaganda by winning four gold medals, a feat unequaled in track and field until Lewis matched it almost a half century later. We'll never know if Owens could have achieved the same longevity Lewis did because he decided to capitalize on endorsement offers after the Games, which at the time made him ineligible for future Olympics.
6. Jackie Joyner-Kersee, USA, Track and Field
Medals: 6 (3 gold, 1 silver, 1 bronze)
How much better is Joyner-Kersee than any other heptathlete before or since? Not only does the world record she set in the Seoul Olympics still stand, she owns the six highest scores ever recorded. Joyner-Kersee owns a silver medal in the heptathlon in 1984 and a pair of golds from 1988 and 1992 in addition to a trio of long jump medals she also earned. She might have one more heptathlon medal from the 1996 Games had she not suffered a hamstring injury at the Olympic trials that prevented her from competing.
7. Michael Johnson, USA, Track and Field
Medals: 4 (4 gold)*
Johnson established himself as the greatest long sprinter in track and field history during the 1990s when he shattered the world records in the 200 and 400 meters and became the only man to win gold in both those events at the same Olympics. Usain Bolt broke Johnson's 200 meters world record (19.32 seconds) in 2009, but Johnson's record in the 400 (43.19) remains one of the most untouchable marks in the sport
* A fifth gold in the 2000 4x400-meter relay was taken from Johnson because teammate Antonio Pettigrew admitted to doping.
[Related: Michael Johnson calls out Oscar Pistorius]
8. Birgit Fischer, Germany, Canoe/Kayak
Medals: 12 (8 gold, 4 silver)
Fischer became the youngest Olympic canoeing champion at age 18 in 1980. She came out of retirement at age 42 to become the oldest Olympic canoeing champion in 2004. In between she won 10 other medals and likely would have won more had East Germany not boycotted the 1984 Los Angeles Games. The legacy she left is as one of the most decorated Olympians of all time regardless of gender.
9. Steve Redgrave, Great Britain, Rowing
Medals: 6 (5 gold, 1 bronze)
You have to be a pretty good rower to by knighted by the queen of England. Redgrave, probably Great Britain's greatest Olympian, received the honor in 2001 after winning gold at five straight Olympics between 1984 and 2000. Only Hungarian fencers Pál Kovács and Aladár Gerevich have won gold at six or more Olympics in a row.
10. Edwin Moses, USA, Track and Field
Medals: 3 (2 gold, 1 bronze)
Moses has the least amount of medals of anyone on this list, but nobody has ever been more dominant than him in his signature 400-meter hurdles. The Morehouse engineering student won 122 straight races from 1976-1987, an incredible streak that included Olympic gold medals in 1976 and 1984 and surely would have in 1980 had the U.S. not boycotted the Olympics. Moses' eight-meter victory over Mike Shine in 1976 is the largest winning margin in the 400-meter hurdles at the Olympics.
Honorable Mention: Greg Louganis, USA, Diver; Jim Thorpe, USA, Track and Field; Nadia Comaneci, Romania, Gymnastics; Al Oerter, USA, Track and Field; Paavo Nurmi, Finland, Track and Field; Natalie Coughlin, USA, Swimming; Nikolay Andrianov, Soviet Union, Gymnastics; Shannon Miller, USA, Gymnastics; John Smith, USA, Wrestling; Alexei Nemov, Russia, Gymnastics.
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