Madrid Open: Rafael Nadal breaks John McEnroe's 34-year-old set record

World number one Rafael Nadal broke John McEnroe's 34-year-old record for successive set wins on a single surface as he moved into the quarter-finals of the Madrid Open.

Nadal, 31, beat Argentine Diego Schwartzman 6-3 6-4 on clay to take his winning streak to 50 sets in a row.

He will play Austria's Dominic Thiem on Friday for a place in the last four.

American McEnroe's 49-set winning run came on carpet in 1984 and included him clinching the Madrid Indoor Open title.

Nadal's 50 sets have included tournament wins in Barcelona, Monte Carlo and last year's French Open.

The Spaniard, looking for a sixth Madrid Open title, faced a minor scare as Schwartzman broke back to make it 4-4 in the second, before Nadal responded immediately and closed out for the match.

"When my career is over, these are things that are going to be there for always," he said afterward.

"They are big records. It's difficult to be able to win 50 sets in a row.

But I've done it. Well, it's done. It's over. Let's not talk about that any more and let's continue on what we have ahead, which is what I am concerned about."

Five-time champion Nadal will next play Dominic Thiem for a place in the semifinal.