Rafael Nadal's path to a record fifth successive French Open title resembled more of a minefield on Friday when he was handed potential clashes with Lleyton Hewitt as well as Spanish compatriots David Ferrer and Fernando Verdasco.
Top seed Nadal will begin his campaign against a qualifier, before a possible third round clash with Australian former world number one Hewitt, who showed his claycourt ability in April when he won the Houston event.
Nadal, who has never lost at Roland Garros, beat Hewitt in the fourth round here in 2005 and 2006.
Claycourt specialist David Ferrer, twice a quarter-finalist, is a possible fourth round opponent with Verdasco a likely last eight rival.
"It's almost a perfect claycourt season. I'm happy with the way I've been playing. The conditions here are different to Madrid where the court was fast and the balls were flying."
Second seed Federer, still searching for an elusive Roland Garros title to add to his 13 majors, and having lost the last three finals to Nadal, starts against Spain's Alberto Montanes.
Old American rival Andy Roddick is seeded to face him in the last eight.
Third seeded Scotsman Andy Murray renews his fierce rivalry with Argentinians when he meets Juan Ignacio Chela, while fourth seed Novak Djokovic, a semi-finalist in the last two years, faces experienced Nicolas Lapentti of Ecuador.
If the seeding works to plan, then Nadal would face Murray in the semi-finals while Djokovic would take on Federer.
Nadal will be happy to see Djokovic in the other half of the draw having had to overcome three match points in a four-hour, Madrid Masters semi-final against the Serbian.
That effort left the Spaniard exhausted by the time he played Federer in the final with the Swiss coasting to his first trophy of 2009.
"I'm mentally and physically fresh," said Federer. "My game is fine, I've practised well and have had no problems in adapting to the different conditions. The win in Madrid was a big boost."
Djokovic is one of the form players on clay this year, finishing runner-up to Nadal in Monte Carlo and Rome and winning in Belgrade.
Serena comes into the tournament under a cloud having lost three times in succession in Marbella, Rome and Madrid. In Spain, she withdrew from her opening match with a knee injury.
"I'm just glad to be here," said Williams. "I'm more confident than I was a couple of weeks ago, so that's a step in the right direction."
Former world number one and 2007 semi-finalist Maria Sharapova, who has just returned from almost 10 months on the sidelines because of a shoulder injury, is unseeded and faces Anastasiya Yakimova of Belarus.
Safina, the winner of the Madrid Open, could face Ivanovic in the quarter-finals.
Safina has lost just once in the 15 matches she has played since becoming number one, winning in Rome as well as Spain.
"If I continue like this I have a very good chance here," she said.
The Williams sisters are in opposite sides of the draw.
Source: AFP Global Edition