George and Tom Burgess (England, league) - The twin towers are part of the four-pronged South Sydney Burgess clan. According to Tom, on joining his twin at the Rabbitohs he was told to shave his hair so others could tell them apart. George also started wearing his socks down for the same reason.
They are very close. Tom has been reported as saying that while time away from each other was tough, it did help them establish individual identities. Physically, they are dead ringers. George tends to start and Tom appears from the bench. They are among the toughest ID missions in sport.
Brett and Josh Morris (Australia, league) - Playing for different clubs and positions - Brett is predominantly a wing for the Dragons and Josh a centre for the Bulldogs - helps split them, but they wore different coloured wrist bands when they started in first grade at St George.
From what can be gleaned, Josh is the talker, Brett is more reserved which is how those in the know split them. But it's Brett who does Twitter, and he's messier. They are rooming together at the World Cup, Josh will be Brett's best man, and they reckon similar injuries strike them in sync. Both are lightening quick and Brett has the edge in representative honours.
James and Hamish Marshall (New Zealand, cricket) - Mum Kate told the Herald only she had never got the ID wrong. Even dad Drew made the odd blooper.
Northern Districts captain Robbie Hart once threw the ball to the wrong Marshall, and they made differentiating tough initially by using the same brand of bat. The Marshalls were only the second test twins after the famous Aussie Waughs, and the first identical pair. They batted in slightly different positions, and James used a lower stance. Both had brief test careers, with Hamish posting by far the better numbers. James retired this year, while Hamish plays on in England and has featured for Ireland.
Saia and Anthony Fainga'a (Australia, rugby) - Like many sporting twins, as close as can be but easy to tell apart as Saia has long hair. Hooker Saia quit the Brumbies and followed Anthony to Queensland when the centre was unwanted in Canberra. Saia is 16kg heavier, which he puts down to being a foodie kid. The elder, he captained an Aussie under-19 side while Anthony was vice-captain. Anthony still braids Saia's hair the night before matches.
Georgina and Caroline Evers-Swindell (New Zealand, rowing) - The Kiwi legends hated being referred to as "the twins". They rowed together, roomed together, even made a quilt together, and retired together. Caroline wore pink jandals, Georgina wore every colour but. Caroline, the stroke, first got into rowing. She admitted to initially and briefly putting hurdles in Georgina's way to put her off and thus retain her new, separate identity. Another difference: some of the media mob regarded Georgina as more chatty. Then again, different folks, different strokes.
Steve and Mark Waugh (Australia, cricket) - As different as sporting twins could be, and not always in the way people expect compared to their image. Mark, the later developer, had one of the great nicknames - Afghan, as in the forgotten Waugh (war). Steve, the outwardly tougher cricketer, was apparently a mischievous kid while the cavalier, elegant batsman Mark was more timid. They reflect life's complexities.
The Waughs didn't hang out or room together on tours, and apparently didn't speak or look directly at each other when batting together. Steve claimed he got premonitions about Mark's dismissals. He was dropped for "Afghan" Mark early in their test careers.
Phil and Tracey Neville (England, soccer and netball) - Easy to distinguish, obviously. Phil (and older brother Gary) found fame with Manchester United and England while Tracey was a standout goal attack for her country.
Like her brothers, Tracey had the misfortune to play in an era when England weren't very good. Phil was an exceptional young sportsman, tipped as being good enough to play cricket for England. Strangely, there's not a lot of interesting stuff about these twins - they tend to say boring, predictable things about each other. But their story is perhaps unique at international level.
Mike and Bob Bryan (US, tennis) - The greatest tennis doubles act in history helped by being mirror twins - Mike is right handed and Bob left. Almost creepily united, they share things such as a bank account, houses and a car. There was one reported physical fight, after a bad Wimbledon, when a guitar was also smashed. They defaulted rather than played each other as kids. The Bryans hint at only minor personality differences and in separate Daily Mail interviews, revealed having the same favourite tennis friends, song, film and food. On court, the slightly bigger Bob is more powerful while Mike is zippier and returns better. When they contemplated singles careers, Bob was the better prospect.
Heinie and Patrick Shannon (New Zealand, softball) - The veteran West Auckland pitcher-catcher pairing helped inspire the Black Sox to the world title this year.
Pitcher Heinie has a famously high pain threshold - urged on by his brother he has defied excruciating injuries that would sideline others to lead province and country to victories. The mirror aspect determined their softball paths - as a leftie, Heinie could not play catcher. Another difference - Heinie smokes while Patrick doesn't.
Mark and Glen Ella (Australia, rugby) - A clear case of one living in the shadow of another. Mark, a five-eighths, is a Wallaby and world rugby great. Fullback Glen played a handful of tests. The famous Aussie coach Bob Dwyer reckoned Glen was the most gifted of all the Ella brothers, but not as confident. He said that although Mark was very talented, his genius came from strong practice.