Rafael Nadal broke John McEnroe's record of 49 straight sets won on the same surface by beating Diego Schwartzman 6-3, 6-4 in the third round of the Madrid Open on Thursday.
Nadal extended his winning streak to 50 consecutive sets on clay, eclipsing the mark McEnroe established on carpet in 1984.
"When my career is over, these are things that are going to be there for always. It's difficult to be able to win 50 sets in a row," Nadal said. "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."
The world No. 1's focus is trained on his next match against Dominic Thiem, a rematch of last year's final. Thiem, who outlasted Borna Coric 2-6, 7-6 (5), 6-4, is the last player to beat Nadal on clay at Rome last year.
"On this surface, (Thiem) is one of the most dangerous players you can face," Nadal said. "Tomorrow is a key match in the tournament."
While Nadal marched on, the top women's players continued to struggle in the Spanish capital after top-ranked Simona Halep and Maria Sharapova both lost in the quarterfinals.
Also on the men's side, second-seeded Alexander Zverev brushed aside Leonardo Mayer 6-4, 6-2 and will meet John Isner after he edged Pablo Cuevas in a hard-fought match that needed tiebreakers to decide all three sets.
Isner prevailed 6-7 (9), 7-6 (3), 7-6 (4) in 2 hours, 21 minutes.
The top-ranked Nadal, who improved to 18-1 overall on the season, has won 38 of his last 39 matches on his favored clay.
Nadal went up a break at 4-2 in the first set after back-to-back errors by Schwartzman, including a missed smash.
Nadal then struck a forehand winner on the run to break Schwartzman again in the second set. Schwartzman broke back, but two straight double-faults gave Nadal a third break en route to the win.
The 16-time Grand Slam champion is seeking his sixth title in Madrid after taking his trophy hauls at Monte Carlo and Barcelona to 11 apiece.
Also, Dusan Lajovic fought back from 0-4 in the decisive tiebreaker to stun fourth-seeded Juan Martin del Potro 3-6, 6-4, 7-6 (6) for his first career win against a top-10 ranked player.
Lajovic moved on to meet sixth-seeded Kevin Anderson, who eliminated Philipp Kohlschreiber 6-3, 7-6 (7).
Kyle Edmund continued his excellent run by ousting eighth-seeded David Goffin 6-4, 6-4. Edmund, an unseeded Brit, defeated former No. 1 Novak Djokovic in straight sets on Wednesday.
Edmund will face 19-year-old Denis Shapovalov, after he bettered Milos Raonic 6-4, 6-4 in an all-Canadian clash.
Halep lost to Karolina Pliskova 6-4, 6-3, ending her bid to become a three-time consecutive champion in Madrid.
Pliskova gave the Romanian no chance, breaking her serve four times and hitting 20 winners.
"I think I played one of my best matches this year for sure, and for sure on clay in my life," the sixth-seeded Pliskova said. "I feel amazing since in the last six matches I lost to her."
Halep got off to a positive start by breaking Pliskova for a 2-0 lead, only for the Czech to take the break right back to swing the match in her favor.
"I missed in some important moments," Halep said. "That's why it went her way."
Pliskova is now the highest seeded player left in the women's tournament after both No. 2 Caroline Wozniacki and third-seeded Garbine Muguruza lost Wednesday.
She will play 10th-seeded Petra Kvitova in the semifinals after she defeated Daria Kasatkina 6-4, 6-0.
Kiki Bertens came from behind to beat Sharapova 4-6, 6-2, 6-3. She will play seventh-seeded Caroline Garcia after she dispatched with Carla Suarez Navarro 6-2, 6-3.