Kenya will be bidding to once again better east African rivals Ethiopia with another dominant display on the track at the London Olympics.

The two traditional powerhouses of middle and long-distance running have enjoyed a spectacular rivalry in recent years, but it is the Kenyan team which is now firmly in the ascendancy.

Formula One's ruling body has this week clarified the rules on dangerous racing moves by drivers defending a position in the heat of a race -- and giving the benefit of the doubt to the man who is leading.

The ruling comes after several controversial incidents this year in which drivers have vigorously defended their positions and in some cases forced challenging rivals off the circuit.

Frenchman Tony Gallopin quit the Tour de France during the race's 13th stage, organizers announced Saturday.

Gallopin, who rides for the RadioShack team, had been suffering from stomach problems in recent days and pulled out inside the first 50 km of the 217 km ride from Saint-Paul-les-Trois-Chateaux to Cap d'Agde.

Former Euro and Africa Cup of Nations winning coach Roger Lemerre was named coach of Algerian First Division side CS Constantine on Saturday, the local press announced.

The 71-year-old Frenchman - who guided France to the Euro 2000 title and then Tunisia to the 2004 Africa Cup of Nations trophy - signed a one year contract with the club, with the option of another year.

Didier Drogba was given a hero's welcome as he arrived in China on Saturday to start a two-and-a-half-year contract that is expected to make him one of football's highest-paid players.

Hundreds of fans, many clad in "Drogba 11" shirts, greeted the former Chelsea star at Shanghai's Pudong airport, some carrying flowers, others brandishing his name in English on placards and many jostling to touch him.

London Olympics organizers said on Saturday that they would investigate claims that workers in a Cambodian Adidas factory were being paid just $61 a month to produce official merchandise for the Games.

The investigation came after Britain's Daily Telegraph newspaper reported that workers at the sportswear brand's factory outside Phnom Penh were making "fanwear" six days a week for a basic salary of $61 (50 euros) per month.

Saudi Arabia's decision to allow two female athletes to compete at the Olympic Games overturns a decades-old taboo imposed by the conservative Muslim monarchy which still bars women from sports at home.

Thursday's announcement by the International Olympic Committee was the fruit of negotiations between the Lausanne-based organization and the kingdom's sports chief and has been hailed as a "breakthrough."

The U.S.-China Olympic rivalry heated up in an unfashionable way Thursday when a top U.S. lawmaker suggested burning the U.S. team's outfits for the London opening ceremony because they were made in China.

"I'm so upset. I think the Olympic Committee should be ashamed of themselves," Senate Majority Leader Harry Reid told reporters when asked about an ABC News report on the origin of the Ralph Lauren-designed uniforms.

Jeremy Lin will be returning to the New York Knicks, according to coach Mike Woodson, the San Antonio Spurs will be hanging onto Boris Diaw and Joe Johnson is leaving Atlanta for the Brooklyn Nets.

NBA player moves continued on Thursday, a day after a moratorium on such signings was ended, with Woodson making it clear that the Knicks would keep Lin despite the four-year offer worth $28.8 million from the Houston Rockets.

Try as they might, rivals of Bradley Wiggins just can't wrest away his Tour de France leader's yellow jersey.

The three-time Olympic track gold-medalist, vying to become Britain's first winner of the Tour, beat back repeated attacks on Thursday in a crucial Alpine stage won by ace French climber Pierre Rolland.