Daniil Medvedev is one win away from retaking the world No 1 spot after moving past American Jenson Brooksby 7-5, 6-1 and into the Miami Open quarter-finals on Tuesday.
The US Open champion lost his serve in the first game but found momentum after fending off two more break points in the fifth, winning the final four games of the first set in which he fired down six aces. He ripped through the second set in less than half an hour, dropping one first serve point.
Medvedev will face defending champion Hubert Hurkacz in the quarters, with a win moving the Russian back to the top ranking on Monday, two weeks after he lost the spot to Novak Djokovic.
"At this moment, I don't feel any pressure," Medvedev said. "To be in the semi-finals, I knew before the tournament that I have to be there if I want to be No 1.
"It's great that I have this chance. Only one match left. Of course maybe during the match, pressure can start to build up, depending on how the match is going ... But at this moment it's just a lot of extra motivation to try to make this one more step."
Kyrgios angrily exits
Australian wildcard Nick Kyrgios lost to Italian Jannik Sinner 7-6, 6-3 after a dispute with the chair umpire.
Kyrgios received a point penalty for bad behaviour in the first-set tiebreak and in between sets angrily and repeatedly asked the chair umpire "What is unsportsmanlike?" before walking to his bench and whacking his racket against the court. The gesture earned him a game penalty, allowing Sinner to open the second set up a break.
Elsewhere in the day's action, fourth-ranked German Alexander Zverev overcame a solid defensive effort from Australian qualifier Thanasi Kokkinakis to win 6-4, 6-4 and set up a quarter-final clash with eighth-ranked Casper Ruud.
The Norwegian, who lost to Zverev in the Paris Masters quarter-finals in November, had earlier sent top British player Cameron Norrie packing 6-3, 6-4 in the Grandstand.
"(Ruud is) somebody that really does not miss much," said Zverev. "He's somebody that tries to play aggressive with his forehand as well. Got to take away his strength in a way and we'll see how it goes tomorrow."
Hurkacz defeated South African Lloyd Harris 7-6, 6-2, while Spain's 18-year-old Carlos Alcaraz battled past Stefanos Tsitsipas 7-5 6-3 in the night session.
Alcaraz, who improved to 15-2 on the season, is one win from consecutive Masters 1000 semi-finals after Indian Wells. He will next face Serbian Miomir Kecmanovic, who beat Indian Wells champion Taylor Fritz 3-6 6-1 6-4.
Argentina's Francisco Cerundolo also advanced to the last eight after beating Frances Tiafoe 6-7(2) 7-6(3) 6-2.
Osaka rolls on
Naomi Osaka thumped 13 aces and 25 winners to dispatch an injured Danielle Collins 6-2, 6-1 to reach the semi-finals, where she will meet Tokyo Olympic gold medalist Belinda Bencic of Switzerland.
Bencic, who beat Daria Saville 6-1 6-2 earlier in the day, has won all three of her Tour-level meetings with the four-time Grand Slam champion, although they have not met since the 2019 U.S. Open.
"I've never had anything to lose against her," Bencic said of her past success against the Japanese star.
"She's the player that has to defend, she has won a lot of Grand Slams, so she's in that position."