Rafael Nadal, the new world number one with an Olympic gold medal in his pocket
For Rafael Nadal's rivals the bad news is that the Spaniard thinks he can get even better.
The 22-year-old woke up on Monday as the new world number one with an Olympic gold medal in his pocket after Sunday's victory over Fernando Gonzalez in Beijing.
Typically modest, or perhaps using some clever kidology, Nadal insisted on Sunday that Roger Federer was still the best player in the world, but the evidence suggests otherwise.
The level of his play at the Olympic Tennis Centre, as it has been for the past six months, was astounding but the Majorcan powerhouse is still not satisfied.
"For me Federer is still technically the best. He is the best player in the history of tennis," Nadal told reporters after his Olympic triumph.
"If Federer can improve, I can too for sure. I can improve the serve 100 percent, I can improve my volley. I'm happy but it's important to be humble if you want to continue improving.
Nadal had barely stepped down from the podium on Sunday before his thoughts turned to the US Open which starts next Monday. Few would bet against him completing a golden quadruple after his French Open and Wimbledon triumphs.
"I don't have time to celebrate," he said. "I have to focus on New York."
From the moment Nadal won his first ATP Tour match as a 15-year-old, his rise to the top of the sport has been widely predicted, although it has still been astonishing in its speed.
He won 11 of his 12 claycourt tournaments in 2005, including his first slam at the French Open. His career defeats on red dust can be almost counted on one hand.
Some doubted whether his extreme grip and massive topspin game which is made for clay could shine on other surfaces.
Three consecutive Wimbledon finals culminating in his epic defeat of Federer this year combined with titles at the big American hardcourt events put that theory to bed.
The contrast between the raging bull that is Nadal on court and the almost sheepish boy next door still surprises those who do not follow Nadal regularly.
Fellow Spanish athletes and those from other countries described Nadal as the friendliest kid on the block in the Olympic Village.
Nadal said nothing would change now that he was the number one player in the world.
"I have very good people around me so nothing will change," he said. "I was happy at number two, I'm happy to be number one."
All eyes will be on Nadal at Flushing Meadows, a venue that has yet to see the best of him. But he will take it all in his stride.
"There's no different pressure now I'm number one," he said. "It doesn't change. I'll probably be number two in a few months ... you never know."