Sweden's Henrik Stenson and Robert Karlsson are eyeing a repeat of their 2008 win at this week's World Cup of Golf but face a strong challenge from Spain, Ireland and England.

Twenty-eight nations will battle for the title at Mission Hills in southern China in the $5.5-million strokeplay team event featuring the likes of Sergio Garcia and Asia's first Major winner, Yang Yong-Eun.

Stenson, ranked seventh in the world, said the team format presented players with a different challenge from what they usually faced.

"I think it's a whole lot of fun just to be able to play in a relaxed, but still competitive mode," he said.

"It's also a great honour to play for your country, and I think that's the most important thing — that we go out there and we represent Sweden," he added.

Highly fancied Ireland feature Graeme McDowell and young hotshot Rory McIlroy, who finished second on the European money list and is ranked number 10 in the world.

McIlroy, just 20 years old, said on Tuesday that motivation would not be a problem despite the disappointment of losing out to Lee Westwood in the battle to win The Race to Dubai to become Europe's number one player.

"I want to play the best I can for my partner. I don't want to let him down. So you know, obviously we are playing for our country which is a huge honour," he said.

"I don't think there would be any reason why you wouldn't be motivated."

McDowell, ranked 51, said he was aware Ireland were among the favourites but added: "Obviously you have no given right to be competing this week. You've still got to go out and play the golf."

"We are both playing great golf, so it's just a matter of going out there and doing it and keeping the energy levels going and keeping the mojo going," he added.

Meanwhile, the United States are aiming to end a nine-year drought at the World Cup with world number 31 Nick Watney saying the barren years show the strength of the world game.

"We are here to try to end that drought," he said. "I don't know if not winning since 2000 is any indication of golf in the United States. I just think it's an indication that everyone else is really good as well."

Spain's Garcia, ranked eighth, is hoping he can drive his team to victory, but knows the competition will be fierce, particularly from the Swedes, who beat Spain by three strokes in 2008.

"There are always a lot of good teams at the World Cup. I think that the Swedish team, the defending champions, will be very good," said Garcia.

England pair the flamboyant Ian Poulter and Ross Fisher for the second year running, both of whom finished in the top 10 on the European Tour money list.

South Korea's Yang, who became a household name in Asia after holding off Tiger Woods to win the PGA Championship in August, will team up with Charlie Wi.

Other potentially strong Asian challenges come from Thailand, who feature Asian Tour regulars Thongchai Jaidee and Prayad Marksaeng, and India, who feature Jeev Milkha Singh and Jyoti Randhawa.

Of the 28 nations that tee off Thursday at Mission Hills, near Shenzhen, 18 will have qualified automatically via the world golf rankings. China will take their place in the field as the host nation alongside nine nations who have qualified through events held in Europe, Asia and South America.

The Omega Mission Hills World Cup is a 72-hole event with each team comprising two players.

The first and third days are fourball, in which four balls are used and the player with the fewest shots takes the hole for their team. The second and final days involve foursomes play, where the teams compete using only one ball per pair.