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Home » Floyd Mayweather lost six times, only once to a world champion

Floyd Mayweather lost six times, only once to a world champion

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World Boxing News looks at the six times Floyd Mayweather lost in the ring as only one conqueror went on to win a world title.

Mayweather has been undefeated for 26 years. So it’s hard to imagine when watching some of his most outstanding performances that he’s lost six times.

As you can imagine, all those reverses came in the amateur ranks. That was way before Mayweather embarked on one of the best careers known to the sport.

Floyd Mayweather

Standing at 50-0 and a five-weight world champion, Mayweather has defeated over 20 world title-holders. He is undoubtedly in the top ten of all time regarding all-around boxers.

Defensively, there’s a firm argument that Floyd is “The Best Ever” as he proclaims himself to be in the media.

Floyd Mayweather returns to the ring this September in another exhibition match-up. The Grand Rapids star’s bid to stay relevant continues as a grandfather.

And, of course, Mayweather will make a nine-figure paycheck into the bargain. They don’t call him “Money” for nothing.


There’s no hope in hell this fall that Mayweather will suffer a seventh career defeat. However, six men in history know how it feels to defeat the great one.

Only one of them went on to become a world champion.

Entering boxing to don a head guard and vest in 1993, Mayweather racked up eleven straight decision wins as a teenage amateur. He immediately put a marker down with his talent to go the distance and win.

In November 1994, a taste of defeat came that Mayweather would never get used to during his tenure.

Defeat 1 – Martin Castillo

Martin Castillo, born Jose Martin Castillo Garcia and nicknamed “El Gallo,” overthrew Mayweather via split decision at the MGM Grand Garden Arena.

Mayweather participated in his first fight at the venue, which eventually became his home.

Castillo only won four of seven bouts in the unpaid code as an American-based Mexican. Immediately following Floyd, he lost to Joan Guzman.

Castillo turned professional in 1998. it was the year Mayweather won his first world title. He entered the paid code around the same weight that he fought the future king.

At super-flyweight, Castillo immediately hit the ground running and became a contender. He amassed a 21-0 record before challenging for the world title.

Losing to Felix Machado, he eventually claimed a version in 2004. Castillo bowed out of boxing in 2010 after failing to countrymen Fernando Montiel and Jorge Arce.

He had made three defenses before surrendering the belt.

Floyd Mayweather amateur

Team USA

Defeat 2 – Carlos Navarro

Two months after suffering his first loss, Mayweather went to the US Pan Am Games in Portland. Unfortunately, not having the ideal preparation, having lost just weeks prior, Mayweather went out in the preliminary round of a tournament he was favored to win.

A southpaw, something Mayweather would be wary of his entire career, Navarro secured his ninth amateur victory on points.

Unlike Castillo, Mayweather would get his revenge ten months later and again the following year.

Navarro went 27-6-1 in the pros, losing to Nate Campbell and Bobby Pacquiao in a career that never boasted a world title.

Defeat 3 – Noureddine Medjhoud

Medjhoud had just lost to Joel Casamayor when Floyd Mayweather crossed his path on a five-fight winning streak.

Mayweather, by now, had fully recovered from his back-to-back losses. But, unbelievably, and competing in only his fourth bout, Medjhoud pulled off the decision.

Fighting just ten times in the amateurs and winning only four, Medjhoud turned pro in 2001 and lost all three of his fights, retiring that same year.

Defeat 4 – Tigran Uzlyan

After a five-month hiatus, Mayweather traveled to Russia for the 100th Anniversary Tournament. By then, he’d acclimatized at the featherweight limit.

Expected to go far again, Mayweather faced shock at the preliminary stage for a second time. Suffering two defeats in a row had become a pattern Mayweather never wanted on his record.

Uzlyan had already had five professional outings when he humbled Floyd in 1995. However, the unheralded Greek Uzlyan eventually re-entered the paid ranks in 2002.

One solitary win was all she wrote.

Defeat 5 – Augie Sanchez

That fourth reverse seemed to galvanize Mayweather as he went on an undefeated run of thirteen fights and began to be more spiteful.

Stoppages became a regular part of his makeup between 1995 and 1996 as the Grand Rapids man aimed to make an impression, ready for the Olympic Games in Atlanta.

At the US Trials in 1996, Mayweather battled Augie Sanchez in the final. He’d already beaten Sanchez a year earlier. He was favored to do something similar.

But in a twist of fate, Sanchez could take the victory and set up a box-off between them later that month in April 1996.

Mayweather won both and went on to the Olympics at the expense of Sanchez.

Sanchez turned pro before the Games began and became a contender at featherweight within two years.

A knockout loss to Edgar Garcia in 1998 did little to derail his world title ambitions as “Kid Vegas” worked his way to a shot at Prince Naseem’s WBO title in 2000.

The exceptional Hamed won via fourth-round stoppage at Foxwoods Resort in Mashantucket.

Two early comeback wins followed until John Michael Johnson ended Sanchez’s career in the first round of a 2001 collision.

Defeat 6 – Serafim Todorov

The most notorious and controversial defeat of Floyd Mayweather’s career came at the Atlanta Games themselves in August 1996.

Mayweather didn’t get the decision despite being on home soil despite seemingly dominating Bulgarian Todorov – a vastly experienced ten-year amateur veteran with numerous medals.

Todorov went on to the final, where he lost to Thailand’s Somluck Kamsing as Mayweather had to settle for bronze.

Briefly turning professional in 1998, Todorov couldn’t adapt to the paid code after so long in the amateurs.

He returned in 2015 in nothing but a money-making event off the back of his “win” over Mayweather.


Speaking about his losses years later to Club Shay Shay, Mayweather was philosophical about how it all went down.

“If I lost six fights all by one point, then there is something to that,” Mayweather said. “But I was fighting on the computer scoring system, so that was difficult.

“As far as how I looked at amateur boxing, it’s a learning program preparing you for the professional ranks if that’s what you choose to do.

“Am I happy with my amateur career? – Absolutely. Am I happy with the Bronze medal and not winning gold? – Absolutely.

WBN Editor Phil has over ten years of boxing news experience. Follow WBN on Facebook @officialworldboxingnews and Twitter @worldboxingnews.