Rafael Nadal has vowed to be ready for his Miami Masters opener in three days after seriously rolling his left ankle on the practice court.

The Spanish second seed suffered the setback on Monday but managed to practise for nearly 90 minutes on Tuesday, although not at full throttle, in a session that gave the 2014 Miami runner-up some much-needed confidence.

But the 28-year-old Spaniard admitted that physios and trainers cannot say with certainty how quickly he can heal.

“At the beginning, I thought it would be the end of the tournament,” Nadal said. “But I think now I’m going to be able to compete here.

“It’s still painful, though I was able to train today. But I didn’t try to push hard. I don’t know how it will be when I when I try to go at 100 per cent, but I’m confident I’m going to be ready.”

Nadal is coming off a quarter-final loss to Milos Raonic last week at Indian Wells.

“It was a loss that didn’t give me negative feeling,” Nadal said. “It gave me energy and positive feelings. I’ve been feeling better each week.”

Nadal said that making it to the court for his Friday match between either Sergiy Stakhovsky or Nicolas Almagro is his only goal for the moment.

“I’m confident I’m going to be ready,” declared the 14-time Grand Slam champion. who is seeded second behind Novak Djokovic.

Nadal said he has not bothered to have a doctor examine the injury.

“I’ve spent time with my physio and the ATP physios. They see things like this every week, and they say it doesn’t look very bad,” Nadal said.

“I can say for sure that I’ll for sure be on the court on Friday. I just don’t know how well prepared I’ll be. I feel I’ve been competing better for the past month and a half.

“This is an important tournament for me. I’m hoping I can train a little bit more tomorrow and then more the day after.

“I feel pain and I was limited a little bit. But the good thing was able to train for 90 minutes, more than I would have expected yesterday. I want be ready to be competitive.”