One of the great things about almost all sports is that they do not discriminate based upon appearances. While the music, movie, TV and many other industries place a heavy focus on looks and appearances, sports, for the most part, cannot. The best boxer will beat the other boxers, regardless of what he looks like. The best striker will score the most goals, regardless of what he looks like. The best sprinter will win the race, regardless of what he looks like. Anyway, you get the point. The only thing that looks will affect are possible endorsement deals the athletes can score away from the field.

Sportsmen may get greater endorsement deals and sponsorship work if they are deemed attractive, but in the field of sport itself, there can be no hiding, you will succeed only if you are capable. Beauty is of course in the eye of the beholder, but most would agree that the gentlemen on this list were not blessed with good looks. The list features men from an array of different sports and backgrounds.

Some of these men were born ugly, whilst others have made some rather unusual editorial decisions upon themselves or simply grown ugly or affected by matters out of their control. Here are the top 25 ugliest male athletes of all time:

25 25. Leon Spinks

Leon Spinks was never a particularly good-looking guy but his appearance really came crashing down when he lost a considerable chunk of his front teeth. The accident is one of many that can be expected as part of the health risks of being a boxer. When your career involves having someone repeatedly try and punch you in the face, you're unlikely to come out unscathed. An Olympic gold medalist and former undisputed heavyweight world champion, Spinks became world champ in only his eighth bout, defeating Muhammad Ali, but lost the title in a rematch seven months later.

24 24. Ronaldinho

There's something charming about Ronaldinho's ugliness. You'll rarely see the Brazilian not smiling, and he made millions across the world smile with his wizardry with the ball at his feet, particularly in the early-mid 2000s. Ronaldinho has had an odd career. He was, most consider, the greatest player on Earth between 2003 and 2007, but unlike most greats of the game, he faded very quickly. In his prime, he was arguably one of the greatest players to ever live. Despite his mammoth reputation and worldwide appeal, Ronaldinho deserves credit for not chasing money all his career. He returned to Brazil in 2011 and currently plays in Mexico. He could have earned far more playing in the Middle East, Asia or the U.S. in his latter years.

23 23. Dennis Rodman

Dennis Rodman has never really gone for a 'natural' look, it is fair to say. Since the early 90s he has dyed his hair more different colors than a Dulux color chart. When green hair no longer sufficed, Rodman began integrating various bits of metal with his face and plastered himself with tattoos. Nicknamed, 'the Worm', Rodman starred for the Detroit Pistons, San Antonio Spurs, Chicago Bulls, L.A. Lakers and the Dallas Mavericks between 1986 and 2000, before returning to basketball in 2003, playing in Finland and the UK, as well as for four U.S. sides, before finally retiring in 2006. He famously caused a stir in 2013 when he visited North Korea and befriended leader Kim Jong-Un.

22 22. Iain Dowie

Former Crystal Palace, Southampton and West Ham striker Iain Dowie has been compared to Sleuth from the Goonies with regards to his appearance. A harsh comparison perhaps, but Dowie was certainly never one of the Premier League's pin-up stars. As a striker, Dowie was never clinical, averaging around a goal every four games even including his time in non-league football. As a manager, he was promoted to the Premier League with Crystal Palace but has struggled everywhere else, and the less said about his punditry work the better. After a harsh review of Dowie, we should point out that he has a masters degree in engineering and was formerly employed by British Aerospace, so well done Iain.

21 21. Chris Kaman

The balding head and ginger-beard combo is a difficult look to pull off, but few fail as miserably as Chris Kaman. What Kaman lacks in good looks he makes up for in height, standing at a whopping 7 feet tall, the German-American has been in professional basketball for 12 years now. Starting off with the Los Angeles Clippers in 2003, Kaman stayed with the Clippers for eight years, before playing for four different teams in four years. These include the New Orleans Hornets, the Dallas Mavericks, the Los Angeles Lakers and his current side, the Portland Trail Blazers.

20 20. Nikolai Valuev

You may have expected someone a little shorter following Kaman, but your expectations would be subverted. Valuev is also over the 7 foot mark, and regarded as the greatest 7 foot+ boxer in history, as a former WBA World Heavyweight Champion. John Ruiz and Evander Holyfield stand out among Valuev's notable scalps, and it was beating the former which made him a world champ twice. Valuev successfully defended the title four times before being defeated by David Haye in 2009. He retired after the fight and has since turned his attention to acting.

19 19. Tyrone Hill

Tyrone Hill played for 13 years in a career which saw him turn out for the Cavaliers, Warriors, Bucks, Sixers and the Heat. Hill's best years were in the mid-90s when he earned an appearance in an all-star game in 1995, and a career best 60.0%, the second highest percentage in the NBA that year. Standing at 6-foot-9, Hill is another tall man to make this list, although that is hardly surprising when of the first six entries, all but one have been either boxers or basketball players.

18 18. Floyd Mayweather Sr.

Father to one of the greatest pound-for-pound boxers of all time, Floyd Mayweather Sr. was a welterweight contender in the 1980s. Maywether Sr. retired with a record of 28 wins, 6 draws and 1 defeat, with his most reputable opponent being Sugar Ray Leonard, to whom he lost in the 10th round. As a trainer, Mayweather Sr. is largely credited with teaching his son the remarkable defense skills which have him unbeaten throughout his entire boxing career and one of the sports greats. Mayweather Sr. is famous for his eccentric dress sense and poetry, but rarely his good looks.

17 17. Frank Gerwer

The only skateboarder to make this list, Frank Gerwer is best known as being the first man to kickflip the Brooklyn Banks stairs and the first man to kickflip the Wallenberg Set. Aged 40, Gerwer is still a professional skateboarder and his real home address is well-known to skateboard enthusiasts as it is the name of his own video game, 'Six Newell'. It's good that Gerwer found a way to make some money while not getting on his board.

16 16. Lorenzo Mata

Lorenzo Mata was a star of the UCLA Bruins men's basketball team from 2004 to 2008, in which time he helped the team to Final Four runs in 2006, 2007 and 2008, before Halcones de Xapala in the LNBP. Mata went into the 2008 NBA draft but went undrafted before a brief spell with the Los Angeles Lakers which proved unsuccessful. Since moving to Mexico he has became an integral part of the national set-up, which won gold at the FIBA Americas Championship. Sadly, none of this alters the fact that many people think Mata looks like one of the Teenage Mutant Ninja Turtles.

15 15. Ezequiel Astacio

Ezequiel Astacio has been described by some as the ugliest Major League Baseball star of all-time. Astacio has been without a team since 2011, when he left the Road Warriors. The 35-year-old pitcher began his baseball career in Philadelphia before joining the Houston Astros in 2003, where he saw his only big league action in the 2005-06 season. In his 100 innings, Astacio achieved 66 strike outs but countered that by giving up 25 home runs.

14 14. Ha Seung-Jin

Ha Seung-Jin is the only South Korean to play in the NBA, and the only South Korean to make this list. Seung-Jin's time in the NBA was brief, and he currently plays for Jeonju KCC Egis in the Korean Basketball League, as well as the South Korean basketball team, with whom he has represented at three different competitions. Standing at an impressive 7-foot-3, Jin is another tall but sadly unfortunate looking chap to make this list.

13 13. Andy Fordham

English darts star Andy Fordham is a former BDO World Darts champion, but has suffered health problems for the last decade. Since as early as 2003 Fordham has struggled with his weight, peaking at 31 stone. Fordham also had issues with alcoholism and doctors revealed at the height of his troubles that 75% of his liver was dead and the other 25% in poor shape, and advised him to stop drinking immediately. Of course, weight troubles and ugliness are not the same thing, but even pre-weight gain Fordham was not blessed with dashing good looks.

12 12. Alex Ovechkin

Alex Ovechkin is one of the best hockey players of his generation, but a looker, he is not. Captain of the Washington Capitals, Ovechkin has played for the Capitals since joining from Dynamo Moscow a decade ago. His finest season came in 2007-08 when he was named both the NHL's top player and MVP, by the Lester B. Pearson Award and NHL Players' Association respectively, but he repeated the feat in 2009. Regarded as one of the toughest players in the NHL, Ovechkin also guided Team Russia to Olympic gold at the 2008 Beijing Games.

11 11. Byron Mullens

British-American basketball player Byron Mullens can currently be found plying his trade in the NBA Development League with Sioux Falls Skyforce. Throughout his career, Mullens has spent time with Oklahoma City Thunder, the L.A. Clippers and the Philadelphia 76ers, as well as playing in both Greece and China. Mullens has an English mother and was set to be a part of the 2012 Great Britain Olympic basketball team before a toe injury ruled him out of contention.

10 10. Carlos Tevez

Carlos Tevez has been one of the most dangerous forward players in world football for a number of years now, combining guile, creativity and industry with goals. It is worth pointing out that Tevez is not on this list due to the unfortunate burning to his neck which occurred as a child, but rather for his face which was not harmed in the incident. Tevez sensationally rejoined Boca Juniors this summer, having guided Juventus to a Champions League final last season. He has played for Boca Juniors, Corinthians, West Ham, Manchester United, Manchester City and Juventus in his career, winning titles with every team he's played for, as well as winning gold with Argentina at the 2004 Olympics.

9 9. Calvin Booth

Two-time Goodwill Games gold medalist with the United States, Calvin Booth had a respectable career with the Wizards, Mavericks, SuperSonics, Bucks, 76ers and the Timberwolves, before ending his career with the Sacramento Kings in 2009. He made the draft in 1999 with the Wizards and featured for the Wizards in the NBA that season and in the 2006-07 season. Just shy of seven feet tall, Booth has a remarkably long and narrow head.

8 8. Russ Grimm

Russ Grimm spent his entire NFL playing career with the Washington Redskins, where he helped the team to four Super Bowl appearances, of which they won three. Grimm was named in the the 1980s NFL Team of the Decade, and named among the 70 greatest Redskins players of all time. Following retirement, Grimm moved into coaching, working with the Redskins, the Cardinals and the Steelers. With an unusually square had and some seemingly misguided hair and mustache choices, Grimm was often considered one of the least attractive NFL players, despite being a star of the league.

7 7. Luke Chadwick

Luke Chadwick showed so much promise as a youngster that Sir Alex Ferguson was reportedly considering making David Beckham a central midfielder rather than a winger, in order to make way for Chadwick on the wing. With searing pace and skill, Chadwick was a big prospect back in 2001, when he played 22 times as Manchester United lifted the Premier League title. However, injuries took their toll, and without his pace, he was a shadow of his potential, dropping down the leagues and continuing to struggle for fitness. Ferguson once described Chadwick as "ugly, but a good player", having been released by Cambridge United, Chadwick may need something else to fall back on now.

6 6. Anthony Davis

The monobrow is not a good look, it just isn't. It doesn't matter how good looking or talented you are, if you have a monobrow, it's just not going to work. Anthony Davis has embraced the monobrow with sayings like "Fear the Brow" and "Raise the Brow", it's still not working. Davis is a fine basketball player, drafted first overall in the NBA Draft and has quickly grown into a franchise player for the New Orleans Pelicans. A two-time NBA all-star player, Davis also won gold with Team USA at the 2012 London Olympic Games.