World number one Rafael Nadal extended his winning streak to 15 matches by beating a defiant Grigor Dimitrov to reach the semi-finals of the Shanghai Masters.

Nadal, riding on the crest of a wave after following up his US Open triumph by claiming the China Open title last weekend, will face Marin Cilic in the last four following a 6-4 6-7 (4-7) 6-3 defeat of Dimitrov.

The top seed needed three sets to beat Dimitrov at the semi-final stage in Beijing last week and it was a similar story as he matched Andre Agassi's tally of 870 career wins to go joint-sixth on the Open Era list.

Dimitrov hit 42 winners to 32 from Nadal, but the sixth seed was unable to prevent a 10th defeat to Nadal in 11 meetings between the two after he was unable to break the favourite's reliable serve in an entertaining quarter-final.

World number nine Dimitrov had the first break-point opportunity in the second game, but Nadal denied the Bulgarian and the Mallorca native was punching the air after unleashing a blistering forehand winner to go a break up at 5-4.

Nadal served out the set and had a chance to gain the upper hand in the second, but Dimitrov saved a break point before taking a 3-2 lead and the pumped-up sixth seed clenched his fist upon winning his next service game.

Both players gave little away behind their powerful serves and a tie-break always looked to be on the cards. Dimitrov was on the ropes at 3-0 down in the breaker, but reeled off five points in a row as Nadal was pegged back after twice drilling forehands into the net under pressure.

Dimitrov raced in to unleash a backhand winner for a break point in the fourth game of the final set, but Nadal thwarted him again and claimed the decisive break to lead 4-2 before sealing yet another win.