Rafael Nadal said fatigue would be his biggest enemy when he led a formidable Spanish men's quartet in the Olympic tennis event starting on Saturday.
The 22-year-old is hoping to add a gold medal to the French Open and Wimbledon crowns he has already bagged this year but just hopes there is something left in his legs.
"I'm very tired but I'm okay, all things considered," Nadal, who will replace Roger Federer as world number one on August 18, told reporters on Wednesday.
"I've only had a week to rest since Wimbledon and before that the schedule was horrifying. I had hardly had any days off.
"I've played well but I've also played many matches. I'm still jet-lagged but I've got a few days to recover. Hopefully, I'll be ready and be able to give my best."
His team mates in Beijing, David Ferrer, Nicolas Almagro and Tommy Robredo, ranked five, 14 and 22 respectively, were unanimous in their praise for Nadal's rise to the top, but the Majorcan said reaching the top was the least of his concerns.
"It's something I've been battling for many years to achieve but right now is not the time for me to enjoy it," he said. "The Olympics is special and I want to live this experience.
"I'm here to represent my country now and the objective is just to win a medal for my country."
Robredo said having Nadal in the Olympic team was a huge boost.
"It's important for Spanish tennis and important for us to have the best player ever from Spain in the team. It's impossible to reach his heights but it's impossible not to be motivated by him -- he motivates every one of us.