Monte Carlo Masters: Rafael Nadal and Kei Nishikori to meet in final

Rafael Nadal has won 13 matches in a row on clay, not losing on the surface since last year's Rome Open against Dominic Thiem

Rafael Nadal produced another clay-court masterclass to beat Bulgarian fourth seed Grigor Dimitrov and reach his 12th Monte Carlo Masters final.

The Spaniard, 31, has won 34 straight sets on his favoured surface after a 6-4 6-1 semi-final victory.

Nadal will play Kei Nishikori in the final after the Japanese world number 36 beat Germany's Alexander Zverev.

Victory for Nadal will be a record-extending 11th triumph at the event and keep him at world number one.

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Nadal needs to win the Masters 1000 tournament, one of the highest-ranked ATP Tour titles after the Grand Slams, to prevent Roger Federer overtaking him.

And few would back him to lose Sunday's final after another ruthless display against an opponent expected to push him closer.

Dimitrov pushed him all the way in an hour-long opening set but was unable to maintain the high levels of mental concentration needed to beat Nadal as the Spaniard ran away with the second set.

Nadal broke the 26-year-old's serve in the second game as he raced into a 3-0 lead, only for Dimitrov to win the next three games as the pair slugged it out in an intense start.

However, the Bulgarian's serve unravelled under the pressure of Nadal being a game away from the set, coughing up two double faults before Nadal hit the line with a forehand winner on his second set point.

Dimitrov failing to win the opener felt like his chance might have gone - and so it proved.

Nadal broke to love in Dimitrov's opening two service games of the second set as the Bulgarian wilted, Nadal serving out to win the second set in 31 minutes.

Nishikori fought back from a set down to beat Zverev 3-6 6-3 6-4 in the second semi-final.

The 28-year-old Nishikori is yet to win a Masters title in three previous final appearances, including one against Nadal in Madrid four years ago when he led by a set and a break before retiring injured.