He's off to a good start.
Federer is through to the quarterfinals, having little trouble on the way to a 6-4, 6-2 victory over 13th-seeded Daniil Medvedev on Wednesday — needing only 61 minutes to prevail in a match where he committed a mere eight unforced errors. The match was supposed to be Tuesday and was pushed back a day because of rain.
So now, to win what would be his fourth Miami title, Federer will have to prevail four times in a five-day span. Next up for the No. 4 seed is a quarterfinal Thursday against No. 6 seed Kevin Anderson — a match between the two highest seeds left on the men's side, and the biggest test yet for Anderson since his return from an elbow issue.
"I'm feeling really good," Federer said. "Today's match, I can be really happy with so I hope it's going to give me some confidence for tomorrow."
Federer and Medvedev split the first eight games, and then things turned quickly. Federer broke Medvedev for a 5-4 lead in the first set, fought off three break points to close out the set in the next game, and got another break to open the second set. He cruised home from there.
"When you want to go deep in tournaments, sometimes you need those 15 minutes that go your way and you're able to pull away with the score too," Federer said of the break and then the rally from 0-40 down to serve out the opening set. "Margins are super-slim and you need a bit of help sometimes from your opponent."
Federer leads the head-to-head against Anderson 5-1, the loss coming last year in the Wimbledon quarterfinals — Anderson winning 13-11 in the fifth set.
"If you beat me at Wimbledon, you've got my attention," Federer said.
Meanwhile, second-seeded Simona Halep also finished her match Wednesday with a flourish.
And a return to the world's No. 1 ranking could be her reward.
Halep beat 18th-seeded Qiang Wang 6-4, 7-5 in the quarterfinals. Halep won the final six games against Qiang and would return to No. 1 in the world if she wins her semifinal match Thursday night against fifth-seeded Karolina Pliskova — a 6-3, 6-4 winner over unseeded Marketa Vondrousova in an all-Czech Republic quarterfinal.
"I just found out from my coach that I need one more match to be No. 1 again," Halep said. "It's pretty much in my head and I'm happy that I'm in this position again."
Pliskova fought off two break points in the final game, then prevailed when Vondrousova sent a forehand long on match point.
"Night, it's perfect for me," Pliskova said.
Pliskova is 2-7 head-to-head against Halep. They are the two highest seeds left in the women's draw; the other women's semi, set for Thursday afternoon, has 12th-seeded Ashleigh Barty against 21st-seeded Anett Kontaveit.
"It's going to be, I think, a good match," Pliskova said of the looming matchup with Halep. "With her the quality of the tennis is always good and the intensity is always good."
Halep has been No. 1 twice before, including most of 2018. She surrendered the ranking to Naomi Osaka in January, and didn't think she would have a chance to grab it back again this quickly.
"It would mean a lot," Halep said.
While Federer is just getting into the quarters, defending Miami champion John Isner of the U.S. became the first man in the field to reach the semifinals and did it in what's become his customary fashion. The seventh-seeded Isner ousted 22nd-seeded Roberto Bautista Agut 7-6 (1), 7-6 (5).
Isner has won 10 straight matches at the tournament and hasn't dropped a set yet in this year's edition at Hard Rock Stadium — 8-0 in sets, 7-0 in tiebreakers. All but one of his sets have been 7-6 wins, the other being a 7-5 triumph. He had 24 aces Wednesday and faced only one break point.
In his seven tournaments this year, Isner has played 47 sets — 24 of those going to tiebreaks.