Preview - Africa's Grand Prix.

This is it: On Sunday in South Africa the most anticipated season in modern motorcycle racing will begin with an inseparable line-up of superstar riders and exotic machines battling to turn pre-season promise into world championship glory.

'Rossi versus Honda' - that's the confrontation everybody's been waiting for, as the five-times world champion turns his powers against his former employer and starts a brave new era with Yamaha.

The 25-year-old's test times on the YZR-M1 have been sensational, given that the machine took just one podium in 2003 and had been widely written off as fundamentally flawed, but its still pure speculation as to whether such pace will translate into race victory after 28 laps in the heat and dust of the Free State gold fields.

Facing Rossi will be an impressive six strong Honda army, riding the latest evolution of the RC211V - a machine that has dominated the premier-class since its introduction in 2002.

The V5 powered beast has been beaten just three times - twice by Yamaha and once by Ducati - but was it the machine or the rider hanging off it for most of those victories (Rossi) that deserves the credit? We'll find out this year...

Of the Honda competitors - Nicky Hayden and Alex Barros (Repsol Honda), Colin Edwards and Sete Gibernau (Telefonica Honda), Max Biaggi and Makoto Tamada (Camel Honda) - only three have ever won a GP, but few can point to any significant weak link in the line-up... save for perhaps the question mark over Tamada's Bridgestone tyres which are likely to be a gift and curse in equal measure.
HRC's biggest headache is probably that they don't have a definitive rider hierarchy established with which to allocate their early season support. The risk, so rivals hope, is that the Japanese giant's efforts will be 'diluted' as they try and keep all six riders in contention before a leader emerges.

But it's not just Honda who will be out to oust Rossi; his own Yamaha colleagues Marco Melandri, Carlos Checa and Norick Abe are sure to benefit from his arrival - and will have nowhere to hide if they are consistently left out of sight by the Italian superstar. However, it's Ducati and, to a lesser extent, Suzuki who are likely to be bigger threats to the impending Rossi/Honda battle...

The Ducati Marlboro Team return for their second season in MotoGP with Loris Capirossi and Troy Bayliss needing to use their irrepressible racing instinct to make up for a frustrating pre-season of development with a brand new version of the Desmosedici.

Both Bayliss and Capirossi have suffered from a lack of track time due to adverse weather conditions, whilst watching newcomers Neil Hodgson and Ruben Xaus make swift progress on their old bikes.

The 2003 World Superbike champion and runner-up form Ducati's first MotoGP satellite partnership, with Luis d'Antin's team. Hodgson is preparing to make his first grand prix start since the 500cc race at Catalunya in 1995 and Xaus his premier-class debut after previous appearances in the 250cc class.

In the Suzuki camp, former world champion Kenny Roberts has been a revelation, putting the new GSV-R, now with Bridgestone tyres, within a fraction of Rossi at the final pre-season test. His team-mate John Hopkins, who regularly outpaced KR JR last season, is fighting to be 100 per cent fit but the pair look capable of taking Suzuki back near the top.

Also impressive in the testing have been the new Kawasaki line-up of Shinya Nakano and Alex Hofmann, whose progress on the radically improved - and now Bridgestone backed - Ninja ZX-RR has done much to inspire fresh optimism at team green.

British Superbike Champion Shane Byrne takes his MotoGP bow with Aprilia - alongside Jeremy McWilliams - where he will be battling to inherit Nicky Hayden's Rookie of the Year title with Xaus, Hofmann and Kurtis Roberts, who has sufficiently recovered from a dislocated shoulder sustained in testing to pilot Proton Team KR's latest V5 machine.

Meanwhile, in the 250cc class, Manuel Poggiali will be hoping for a repeat performance from last season's event if he is to hold off the challenge of Randy De Puniet.

The eventual World Champion fought for victory with the Frenchman at Welkom one year ago and, after dominating virtually every single test session throughout the preseason, De Puniet is showing strong signs that this could be the year his undoubted raw talent transcends to the consistency and class of a serious title contender.

The Aprilia pair, who are joined in the Italian factory ranks this season by promising youngster Alex De Angelis and Grand Prix winner Sebastian Porto, as well as the continued presence of Fonsi Nieto, will face a barrage of competition from rival factory Honda, who have doubled their efforts for quarter-litre glory in 2004.

After prising Toni Elias from Aprilia to join Roby Rolfo in the factory team, the Japanese manufacturers are also laying on two extra official bikes for 125cc world champion Dani Pedrosa and 250cc Japanese champion Hiroshi Aoyama.

Elsewhere, strong privateer challenges are expected from Campetella Racing, who have snapped up promising youngster Joan Oliv? to form a three man line-up alongside last season's podium regulars Franco Battaini and Sylvain Guintoli, and the Equipe de France, who have signed former 125cc World Champion Arnaud Vincent for his first season at quarter-litre level.

In the 125cc class, Hector Barbera starts the season looking to raise the Spanish flag at the Phakisa Freeway, just as eventual champion Pedrosa did last season.

The Aprilia teenager, who is now the highest ranked rider in the class, and his team-mate Alvaro Bautista have been the men in form during preseason and are looking to secure early success for the team formed just a couple of seasons ago by top Dutch footballer Clarence Seedorf.

Honda's main hope of defending the title appears to lie in the form of promising Italian Andrea Dovizioso, who finished second at Welkom last season, whilst KTM are gunning for glory in just their second season after clinching the signature of Casey Stoner, winner of the final race of 2003.

The return of experienced former world champion Roberto Locatelli and Youichi Ui's decision to stay for one more attempt at the minor category title adds guile and experience to an explosive young field, which features no fewer than fifteen teenagers.