Djokovic beats Dolgopolov 6-7 (3), 7-5, 6-0 at Miami Open

KEY BISCAYNE, Fla. — Novak Djokovic rallied from a set and a break down Tuesday to beat Alexandr Dolgopolov 6-7 (3), 7-5, 6-0 in the fourth round of the Miami Open.

Dolgopolov led 4-1 in the second set before the No. 1-ranked Djokovic mounted a comeback to remain in contention for his fifth Key Biscayne title.

After the second set, Dolgopolov received treatment from a trainer, who bandaged the soles of both feet. Dolgopolov moved poorly after that and won only three of 27 points in the final set.

As Djokovic fell behind in the first set, he busted a racket in anger, drew jeers from the crowd and was cited for two code violations, which cost him a point penalty. But he won a succession of long exchanges late in the second set that allowed him to pull even with Dolgopolov.

"The first set and a half, he was dominating from the baseline," Djokovic said. "I was frustrated and nervous and wasn't showing composure on the court."

Andy Murray became the ninth active man to win 500 matches by beating Kevin Anderson 6-4, 3-6, 6-3. Murray, who improved to 500-155, is the 46th man to reach the milestone during the Open Era, and the first from Britain.

"I don't know why, but getting to 500 gives me motivation to go on and try and win more," Murray said. "I hope I've still got a lot more wins in me."

The No. 3-seeded Murray, who won the Key Biscayne title in 2009 and 2013, was presented with a cake in a postmatch ceremony. He next plays unseeded Dominic Thiem of Austria, who beat No. 28 Adrian Mannarino 7-6 (5), 4-6, 7-5.

Djokovic next plays No. 6 David Ferrer, who beat No. 12 Gilles Simon 7-6 (5), 6-0. No. 4 Kei Nishikori, who has lost 10 games in his three matches, eliminated No. 18 David Goffin 6-1, 6-2.

No. 8 Tomas Berdych advanced when No. 17 Gael Monfils fell and hurt his hip. Berdych was leading 6-3, 3-2 when Monfils retired.

Monfils, seeded 17th, said he bruised his hip but hopes to be able to play in his next scheduled tournament in Houston.

Next up for Berdych is unseeded Juan Monaco of Argentina, who beat No. 29 Fernandez Verdasco 6-3, 6-3. Verdasco was coming off an upset win over Rafael Nadal.

In women's play, No. 9 Andrea Petkovic became the first semifinalist when she beat No. 14 Karolina Pliskova 6-4, 6-2.

To beat the 6-foot-8 Anderson, Murray relied on lots of defense and just enough offense. He scrambled all over the court to keep points going, and in the final game made improbable saves to extend rallies on consecutive points, winning both.

When Murray broke for a 3-1 lead in the final set, he screamed "Come on!" loud enough to startle any sunbathers across the street on Crandon Beach. He easily held from there, winning 12 of 13 points in his final three service games.

"In the third set I created quite a lot of chances, and served better as well," Murray said.

While Anderson had the bigger serve, Murray lost only eight points on his first serve.