Rafael Nadal needed three sets to defeat Bulgarian Grigor Dimitrov and reach the last four of the Shanghai Masters ©Getty Images

World number one Rafael Nadal needed three sets to defeat Bulgarian Grigor Dimitrov and reach the last four of the Shanghai Masters.

The 31-year-old Spaniard, a 16-time grand slam champion, is seeking a maiden title on the hard courts at the Qizhong Forest Sports City Arena in the Chinese city.

This year's French Open and US Open champion did not have it all his own way at the Association of Tennis Professionals Masters 1000 tournament, winning 6-3, 6-7, 6-3.

Nadal, the top seed, has now booked a semi-final date tomorrow with Croatia's fourth seed Marin Čilić.

The 2014 US Open champion knocked out Spain's unseeded hopeful Albert Ramos, 6-3, 6-4.

Roger Federer continued his run to the last four ©Getty Images
Roger Federer continued his run to the last four ©Getty Images

A blockbuster final between Nadal and his perennial rival Roger Federer remains on the cards as the Swiss also won his quarter-final.

Federer, who won in Shanghai in 2014 and boasts 19 grand slam victories, beat France's Richard Gasquet 7-5, 6-4.

He will now face Argentina's Juan Martin del Potro, the 2009 US Open champion and Rio 2016 Olympic silver medallist who came from behind to end the run of Serbia's Viktor Troicki.

The Argentine recovered from a slow start to triumph 4-6, 6-1, 6-4.

The last four contests will be held tomorrow.

Britain's Andy Murray and Serbia's Novak Djokovic, who have won six out of the last seven editions between them, are both absent due to injury.