Rafael Nadal stretched his winning run on clay to a record 50 consecutive sets to reach the Madrid Open quarter-finals at the expense of Diego Schwartzman.

The world number one surpassed John McEnroe's Open Era mark of 49 straight sets won on a single surface - set on carpet back in 1984 - to seal a 6-3 6-4 victory at the Caja Magica on Thursday.

Nadal has now won 21 consecutive matches on the red dirt after another stunning exhibition in his homeland, Schwartzman putting up a strong fight but failing to deny the Spaniard another entry into the record books.

The 16-time grand slam champion will face Dominic Thiem, the last man to beat him on clay at the Internazionali d'Italia in 2017, in the last eight as he attempts to win the tournament for a sixth time and claim a third consecutive title following his triumphs in Monte Carlo and Barcelona.

Schwartzman got himself out of trouble to hold after saving two break points in his first service game and put Nadal under pressure in the next game, the defending champion also saving a break point before taking a 2-1 lead.

The top seed did not have too long to wait for the only break of the first set, Schwartzman making a mess of a simple overhead volley and crashing a backhand into the net to trail 4-2.

Schwartzman's timing was out and he was unable to prevent Nadal from taking a 49th consecutive set on his favourite surface, which was sealed when the Argentine steered a tame return into the tramlines. 

There was a gasp when Nadal missed a straightforward forehand early in the second set and a roar when Schwartzman put away a rasping forehand winner down the line, but the 'King of Clay' broke to lead 3-2 with a thunderous effort. 

Schwartzman was not finished yet and broke for the first time to level at 4-4 after giving Nadal the runaround with some powerful groundstrokes off both wings. 

Nadal must have forgotten what it feels like to go to the distance, though, and a double fault from Schwartzman put the Mallorca native back in front and he was jumping for joy after serving out the match to make history.