Twins start out their existence as womb mates. With a bond like that, it should come as no surprise that later they become playmates, roommates and, in some cases, teammates.
Many sets of twins become impassioned with the same sport. They partner up, or they face off against each other. As fans, we are intrigued. Can they anticipate one another's moves? Is one dominant over the other? Do they feel one another's pain?
While we may never be let in on such answers, one thing is for sure: History has churned out a number of twin siblings with notable careers in professional sports.
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While Angela and Amber have no wins, no top finishes and no poles between them, they are notable in that, in 2010, they became the first set of twins to compete in a national division NASCAR race.
Their uncle is 1990 Daytona winner Derrike Cope.
After stellar high school and college basketball careers, both sisters were drafted into the WNBA in 2001. Kelly is the older of the two by four minutes. Neither twin is in the WNBA at the moment, as their respective teams waived them right around the same time in 2012.
Rafael and Fabio, who both play for Manchester United, look so much alike that once a ref cautioned Rafael for a Fabio foul.
Some identical twins strive to differentiate themselves from their sibling, others embrace the two-of-a-kind thing. The Morris' fall into the latter category. They own the same car, rock the same beard, have the same tats and now, after a year apart, are on the same team—the Phoenix Suns.
The Suns, who can now safely be called the twin-friendliest team in NBA history (twins Dick and Tom Van Arsdale played together with the Suns in 1976-77), traded with Houston to acquire Marcus.
Hey, there's only so much two people can share—even twins. The Brazilian Nogueira twins share a face, a given name, a family name and a love for martial arts.
Perhaps that is why they decided not to share an MMA division.
Antônio Rodrigo (aka Minotauro) weighs in at 237 pounds and is 34-8-1 as a heavyweight.
Antônio Rogério (aka Minotoro) weighs in at 205 pounds and is 25-5-0 as a light heavyweight.
Sport: Basketball (high school)
The high school dynamic duo will be joining the potent University of Kentucky freshman class this fall. Word is still out on how well they will play against the big boys.
But if Andrew was really as good as he thinks he is (he apparently claims that he could have taken down MJ in his prime), it'd be enough to move these boys to the top of this list.
No doubt whatsoever who carries this duo. Tabling the whole juicing matter, José had a legendary MLB career. He made the All-Star team six times, won two World Series titles, won four Silver Slugger Awards and has a resume chock full of additional accolades.
Ozzie, well, he played in just 24 games in the majors, then was sent on a bus to live out his days in Scrubs-ville.
The formidable snow twins represented the U.S. in three Winter Games: 1976, 1980 and 1984.
In the 1980 games, Phil took home a silver medal for slalom. In the 1984 games, both brothers medalled in slalom—Phil with gold and Steve with silver.
Also, Jason has earned himself a spot in history as the first active male professional athlete in a major North American team sport to come out publicly as being gay.
Devin has made a decent splash in his NFL career as a New England Patriot; during his rookie year, he picked off seven passes and finished second in Rookie of the Year voting.
Twin seven-footers. Stick an antennae on each of their heads, and you might mistake them for the Petronas Towers.
The brothers both entered the NBA after their sophomore seasons at Stanford.
Brook, a center, has played five seasons for the Nets, has a career average of 17.9 points per game and made his first All-Star appearance in 2013.
Robin, also a center, was recently traded to the Portland Trailblazers, where he hopes to build off his career-best year in 2012-13.
In his three years in the NFL, younger twin Maurkice (by 60 seconds) has already become an integral part of the Steelers squad. He's played in 45 games in three seasons, was named Steelers Rookie of the Year in 2010, has been named All-Pro for all three of his years and been invited to the Pro Bowl for all three years.
Mike followed his brother into the NFL a year later and was selected by the Miami Dolphins in the 2011 draft. He's played 32 games to date and has one fumble recovery.
Tom played for 12 season in the NBA, made three All-Star appearances and ended with a career average of 15.3 points per game.
Dick played for 12 seasons in the NBA, made three All-Star appearances and ended with a career average of 16.4 points per game.
The story of the Van Arsdales in the NBA came to a sweet ending when they played their final season together as Phoenix Suns in 1976-77.
Rich and Ron are just two of the six Sutter brothers who played in the NFL (a seventh, Gary, did not). During the 1983-1984 season, Rich and Ron, both playing for Philadelphia, became the first set of identical twins to suit up for the same NHL team.
Sport: Slalom Canoe
The Hochschorner brothers from Slovakia are the most decorated athletes in Olympic canoeing history, taking the gold in the Sydney in 2000, in Athens in 2004 and in Beijing in 2008. They were dethroned in the London 2012 games but still took home a bronze.
Both undefeated as light middleweights, the Charlo brothers hope to make history as twin champions. If so, they may find themselves squaring off against one another in the ring some day for a championship belt.
You thought the Harbowl was the ultimate in sibling rivalry? Just wait.
Joel, a center, has played just 134 regular-season games and 25 playoff games (with the Dallas Stars) in the league. He currently plays in the Swedish professional league.
On Dec. 14, 2006, the brothers played each other (pictured here) in a Rangers vs. Stars matchup. The Rangers won 5-2. And no, Joel didn't score on his bro.
Often cited as the most successful twins in the history of soccer, the de Boers played together at five clubs: Ajax, Barcelona, Rangers, Al-Raygan and Al-shamel.
They won a UEFA Champions League title together in 1995.
They have a combined 179 caps for the Dutch national team (Frank 112 and Roland 67) with 13 goals scored each.
The Sedins have long been staples of the Vancouver Canucks; in fact, Henrik is the current team captain. He holds numerous team records, including the all-time leading scorer.
Daniel, too, has numerous accolades. In 2011, he was the regular-season leading scorer (104 points) and was voted the Most Outstanding Player.
The Waugh twins (pictured here with younger brother Dean) are easily the most famous twins in the sport of cricket.
Steve was captain of the Australian test cricket team from 1999 to 2004. He turned an already formidable team into an unstoppable one. With 168 test appearances, Steve was the most capped player until his record was overtaken in 2010 by India's Sachin Tendulkar.
According to his ESPN bio, Mark "was one of the world's most elegant and gifted strokemakers in the game."
In 1891, at age 19 years and five months, Wilfred stunned the tennis community by winning the singles title at Wimbledon and becoming the youngest player to hold that title. The record stood for 94 years (snatched away by a 17-year-old Boris Becker in 1985). That same year, Wilfred and Herbert took the doubles title.
Wilfred won two more Grand Slam singles titles (1892 and 1895) and three more doubles titles with Herbert (1894, 1895 and 1896).
Ronde spent his entire 16-year NFL career with the Tampa Bay Buccaneers. Perhaps most impressive among the numerous accolades he racked up is his membership in the one-member-strong 40/20 club (40-plus interceptions, 20-plus sacks).
Tiki also played his entire NFL career (10 years long) with a single team—the New York Giants. As a running back, Tiki became one of the the Giants' all-time greats. He holds the following team career records:
- Rushing yards with 10,449
- Rushing touchdowns with 55
- Rushing attempts with 2,217
- Receptions with 586
- Total yards with 17,359
With a Wimbledon win in July 2013, the twins became only the second team in history to win all four major doubles titles.
Mike has 93 doubles career titles; Bob has 91. They won Olympic gold in the London Games.
They are so coordinated and in sync on the court that opponents have actually wondered if they communicate with some sort of secret twin telepathy.