Beijing:Rafael Nadal sent out a stark message of intent to contenders for the Olympic singles crown with a crushing 6-1, 6-2 defeat of Australian Lleyton Hewitt here on Tuesday.
The Spanish number two seed, who will take over as men's world number one next week, asserted full control of the match early on, breaking Hewitt at 2-1 up in the first set.
The Australian, former number one, had played a grueling doubles match that stretched into the early hours of Tuesday after going to 18-16 in the third set, and his tiredness showed, notably on his backhand returns.
Hewitt, currently ranked 38 in the world, managed to break Nadal in the first game of the second set in a short-lived revival but the Spaniard stole the march again and soon had the match wrapped up.
Also in blistering form on Tuesday were the Williams sisters and the Serbian duo of Jelena Jankovic and Novak Djokovic.
Jankovic, the women's world number one and Olympics top seed in the absence through injury of Ana Ivanovic, beat Ukraine's Alona Bondarenko 7-5, 6-1.
The Serbian broke Bondarenko three times in the second set and put the match away with a lightning backhand pass down the line.
The 23-year-old from Belgrade was wearing a strapping on her troublesome right calf and did not look completely at ease but said she hoped it would continue to get better.
"I took some painkillers to be able to play, otherwise it's quite sore," Jankovic said.
"It was already much better than yesterday when I was in a lot of pain. But today it was better and I hope to be improving further for Wedensday."
Jankovic's compatriot Djokovic, seeded third in the men's draw, progressed confidently against Germany's Rainer Schuettler 6-4, 6-2.
But Russian fourth seed Nikolay Davydenko crashed out 7-5, 6-3 to Paul-Henri Mathieu.
Mathieu will join French compatriots Gilles Simon, the 10th seed, and Gael Monfils in the third round after their respective wins over Guillermo Canas of Argentina and Romanian Victor Hanescu.
There was also a win for 17th-seeded Czech Tomas Berdych over Italy's Andreas Seppi, and a win for Belgian Olivier Rochus who was a set ahead of Janko Tipsarevic when the Serbian retired injured.
The Williams sisters both earlier confirmed their status as among the hot favourites for gold in the women's singles, which has been hit by a raft of withdrawals.
Fourth seed Serena took just 44 minutes to dispatch Australia's Samantha Stosur, the American eight-time Grand Slam champion breaking at 3-2 and taking complete control to reel off the last 10 games to love.