Rafael Nadal has enjoyed a lot more serving success than we’ve ever realised.

The Spaniard is widely regarded as one of the best all-time when returning and competing from the back of the court, but he rarely receives the recognition he deserves as a server.

An Infosys ATP Beyond The Numbers analysis reveals Nadal has won a higher percentage of his second-serve points than anyone else in the game. Nadal’s second serve is not as powerful as many of his opponents’, but his heavy, lefty slice makes his second serve extremely difficult to attack.

He typically targets the opponent’s less potent backhand return of serve, jamming the serve into the body to elicit a neutral return down the middle of the court. Aiming at the body also keeps the serve away from the singles sideline and the center line, where double faults often occur. Nadal’s favourite way to build the point is with a “Serve +1 forehand”, which helps him quickly gain the upper hand as he pushes opponents back and then side to side.

The left-hander has won 56.9 per cent of his second-serve points throughout his career, slightly edging arch-rival Roger Federer, who has won 56.6 per cent.

Only four of the Top 10 leaders in this specific category would be classified as “big servers” – players widely renowned for their ability to drop heat on both first and second serves. John Isner, Andy Roddick, Milos Raonic and Wayne Arthurs all made the Top 10 list.

Top 10: Second-Serve Points Won

Four other players in the Top 10 list have learned how to maximise their efficiency in this key category. Novak Djokovic, Juan Carlos Ferrero, Andre Agassi and Philipp Kohlschreiber all backed up solid second serves with devastating groundstrokes.

Season Leader

Federer finished first in second-serve points won five times, with Djokovic, Nadal and Roddick also taking end-of-season honours at least once during the past 10 seasons, according to the ATP Stats LEADERBOARDS.

The Infosys Information Platform also uncovered that Djokovic’s inspiring 2015 season, when he went 82-6, won 11 titles and took home more than $21 million in prize money, was fueled by second-serve domination. Djokovic won an astonishing 60.2 per cent of his second-serve points last season, the highest percentage anyone has achieved in the past decade.

Japan’s Kei Nishikori survived a scare on Monday to advance to the third round of the Rio Olympics. Aussie John Millman was up a break in both sets, but the fourth seed came back to win 7-6(4), 6-4.

Millman, No. 74 in the Emirates ATP Rankings, served for the first set at 5-4 but was broken. He also led 4/0 in the tie-break, but Nishikori roared back to win seven straight points and take the first set. The 27-year-old Millman also led 4-3 in the second set, but lost his next two service games.

Nishikori will next face Slovakia’s Andrej Martin, who received a walkover when German Philipp Kohlschreiber withdrew because of a right foot injury.

Juan Martin del Potro backed up the biggest upset of the Olympics with another strong performance. The Argentine moved into the third round with a 6-3, 1-6, 6-3 win against Portugal’s Joao Sousa, No. 36 in the Emirates ATP Rankings. Del Potro struck 13 aces and lost only two points on his serve (20/22) in the third set. The 27 year old also bullied play with his forehand, hitting 16 forehand winners compared to one from his backhand side.

The 6’6” right-hander, who has struggled with wrist injuries over the past few years, will look to reach the quarter-finals in Rio when he faces Japan’s Taro Daniel, who swept #NextGen player Kyle Edmund of Great Britain, 6-4, 7-5. Del Potro started his Olympics with a 7-6(4), 7-6(2) victory against World No. 1 Novak Djokovic.

Luxembourg’s Gilles Muller hit 14 aces to prevail over fifth seed Jo-Wilfried Tsonga 6-4, 6-3. It’s the latest big win for Muller, who’s reached two of his five career ATP World Tour finals this season.

Muller, who carried the flag for his home Luxembourg in the opening ceremony, will try to continue his best Olympic run when he faces 10th seed Roberto Bautista Agut in the third round. Muller fell in the second round in London in 2012. Bautista Agut denied Italian Paolo Lorenzi 7-6(2), 6-2 in 89 minutes.

Ninth seed Marin Cilic swept his way into the third round, dispatching Moldova’s Radu Albot 6-3, 6-4. The top Croatian broke Albot four times and will next face Frenchman Gael Monfils, who upset the home crowd by beating Brazilian Rogerio Dutra Silva 6-2, 6-4 in 73 minutes. Monfils is coming off his first ATP World Tour 500 title at the Citi Open in Washington and a runner-up finish at the Rogers Cup (l. to Djokovic), an ATP World Tour Masters 1000 in Toronto.

Read More: Monfils Outlasts Karlovic For D.C. Crown

DOUBLES

Rafael Nadal won for the second day in a row in Rio, pairing with Marc Lopez to beat del Potro and Maximo Gonzalez 6-3, 5-7, 6-2. Nadal won his first-round singles match on Monday. The Spaniards will next face Austrians Oliver Marach and Alexander Peya, who outlasted Americans Rajeev Ram and Brian Baker 6-4, 6-7(2), 6-3.

Home favourites Marcelo Melo and Bruno Soares swept past Serbians Novak Djokovic and Nenad Zimonjic 6-4, 6-4. The third seeds will face the fifth seeds, Romanians Florin Mergea and Horia Tecau, who beat Mexicans Santiago Gonzalez and Miguel Angel Reyes-Varela 6-3, 7-6(9).

Americans Steve Johnson and Jack Sock defeated the Colombian team of Juan Sebastian Cabal and Robert Farah 6-4, 7-6(1). Johnson/Sock will face Bautista Agut and David Ferrer, who beat Lukasz Kubot and Marcin Matkowski of Poland 6-3, 7-6(5).