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South African LJ van Zyl is in the form of his life, having twice run a personal best of 47.66 seconds - the fastest time in the world this year. He has also sparkled at the Diamond League meetings in Doha and Rome.

Britain's Dai Greene won European and Commonwealth gold last year but is yet to hit top gear in 2011. He has only raced twice competitively, finishing second to Van Zyl on both occasions. Bershawn Jackson, the former world champion, heads the USA's domestic charge. Now aged 28, he is currently the third quickest American this season and will be keen to demonstrate he is still top dog on home soil.

An intriguing race pits America's former Olympic and two-time world champion Jeremy Wariner against the raw talents of Grenada's Rondell Bartholomew and Bereket Desta of Ethiopia.

Bartholomew is quickest in the world this year with an impressive 44.65, while Desta is only fractionally slower. Both aged 21, they have come of age in 2011 - breaking the 45-second barrier for the first time. Calvin Smith, a Diamond League winner in Shanghai, is also in the line-up.

There is an Anglo-French rivalry on the New York runway, albeit a friendly one, as Britain's Phillips Idowu once again takes on young French sensation Teddy Tamgho. World champion Idowu recently had his world-leading distance eclipsed by Tamgho but insists he is good friends with the 21-year-old and looks on him as a little brother.

The two men have been sparring for the world number one ranking all season and already have one Diamond League victory apiece. New York was the scene of Tamgho's huge 17.98m leap last year - the third best of all-time. Former Olympic and world champion Christian Olsson of Sweden also competes in a highly competitive field.

Heptathlon world champion Jessica Ennis excels in the sprint hurdles, as she proved when beating former world number one Lolo Jones indoors earlier this season, but she will have to be at her best to feature prominently in this company.

The USA's Kellie Wells is the form athlete of 2011. She has already enjoyed Diamond League success in Doha, winning in a new lifetime best and world-leading time of 12.58. Former world champion Perdita Felicien of Canada should also be close to the front, while American-born Briton Tiffany Ofili-Porter is the fourth fastest in the field this season.

Three-time world champion Allyson Felix has not been at her best since beginning the year with a season's best time of 22.38 in the South Korean city of Daegu, the venue for this year's world championships.

The American could subsequently only manage fourth place in Rome's Diamond League meeting in a race won by her 22-year-old compatriot Bianca Knight. Also in action Jamaicans Shelly-Ann Fraser and Sherone Simpson, the respective Olympic 100m gold and silver medallists from Beijing, and the US sprinter Carmelita Jeter, the fastest 100m runner this year.

America's number one sprinter Tyson Gay is guaranteed a hero's welcome in front of his home fans. The 2007 world champion over 100m and 200m is the current world number one at the shorter sprint following his blistering run of 9.79 in Clermont earlier this month.

In the absence of Usain Bolt, the Jamaican charge is led by Steve Mullings, who ran a career-best 9.80 last week. Mullings' compatriot and training partner Nickel Ashmeade is also a name to keep an eye out for. The 21-year-old has improved his personal bests this year in both the 100m and 200m, and has beaten several more established sprinters en route.