By Steve Gorten

KEY BISCAYNE – It appeared that David Ferrer’s 33rd birthday Thursday might end with a big celebration at night.

Playing the world’s No. 1 player on stadium court, the seventh-ranked Spaniard captured four of the first five games of their men’s quarterfinal at the 2015 Miami Open.

But despite Ferrer’s strong start, Novak Djokovic won here yet again, moving closer toward his fifth Miami Open title with a hard-fought 7-5, 7-5 win.

“I wasn’t feeling the ball that great at the beginning, but I knew that I’m going to have my chances if I stayed committed, if I kept on working,” Djokovic said. “But I had to earn my points. I had to fight for everything that I got tonight on the court, because he wasn’t going to give it to me. I knew that coming onto the court. I knew that he’s a great competitor, that he grinds a lot, runs, and makes you play always an extra shot. That’s why he’s been top‑10 player for so many years and he’s tough to beat.”

Djokovic, who hasn’t lost at Crandon Park Tennis Center since a fourth-round loss to Tommy Haas in 2013, is trying to become the first player to win both Indian Wells and Miami in the same year three times.

He will next face American and world No. 24 John Isner in the semifinals.

Thursday’s win marked Djokovic’s eighth consecutive against Ferrer, whom he has beaten 14 times in 19 matchups all-time.

After surrendering a set in two of his previous three matches, Djokovic fell behind early against Ferrer, but broke his opponent’s serve at 2-4 in a game that lasted 10 minutes. Djokovic would break Ferrer’s serve three more times in the match.

“Djokovic, in important moments, played good,” Ferrer said. “End of the first set, he was very good with his shots. In the second, he was better than me.”

Ferrer said he needs to be aggressive and “play perfect” on crucial points to beat Djokovic. He wasn’t aggressive enough Thursday. He was able to survive a match point with Djokovic serving up 5-4 in the second set, but couldn’t force a third set.

Ferrer, the sixth seed at this tournament, won his first three matches here in straight sets, losing just 17 games combined.

Djokovic said after his fourth-round win that he was worn down. After his win Thursday, though, “I felt physically pretty good. Mentally, also tough,” he said. “I regained my strength as I had a day off, which I knew was going to serve me well. Now, playing again [Friday], it’s going to be a huge mental challenge for me. But I look forward to it. This is the final stages of a big event, and this is what I came here for, to play the big matches.”