World No.1 Rafael Nadal has praised Japan's Kei Nishikori and tipped him to break into the top 10 following their hard-fought encounter at the Australian Open.
The Japanese star kept Nadal on court for three hours 17 minutes before going down 7-6 (7/3), 7-5, 7-6 (7/3) in the fourth round.
Nishikori said he was proud of his efforts, but also disappointed to lose his sixth straight match to Nadal and failed to take a set, Sport24 reports.
Nadal said Nishikori had come a long way in a short time and had a bright future.
He said Nishikori is a very complete player and is very quick, and has the ability to do the most difficult thing in tennis.
Nishikori, who is currently ranked 17, is presently being coached by former French Open champion Miachel Chang.