Nadal has already won this year's first Grand Slam in Australia
World number one Rafael Nadal has booked his place in the end-of-season ATP World Tour finals, which will be staged in London in November.
The 22-year-old's fine start to the season has earned him enough points to secure his spot where he will be joined by the world's top seven other men.
"To qualify was one of my goals and shows this season has already been a great success for me," said Nadal.
"London brings me great memories and the fans really support me each year."
This year's event will take place from 22-29 November at the O2 arena in London.
Nadal was beaten by Roger Federer in the final of the Madrid Open last week but has already won the first Grand Slam of the tour in Australia along with the Masters Series events in Indian Wells, Monte Carlo and Rome.
However the Spaniard's place was not confirmed until now, even though he had already won a Grand Slam, as it is only the top eight men in the world who qualify.
Nadal, who missed last season's World Tour finale in Shanghai (then Tennis Masters Cup) because of tendonitis in his knee, is likely to be joined by world number two Federer, Andy Murray and reigning champion Novak Djokovic among others in London.
The round-robin event will have a prize pot of $5m (£3.2m), with 1,500 ATP world ranking points going to the winner.
"History shows us that players love playing in this event and I'm very confident that everybody who qualifies will want to be here," said tournament director Brad Drewett.
"The depth of talent in men's tennis at the moment, with the likes of Federer, Nadal, Murray and Djokovic means that fans can expect to see some epic tennis."