Novak Djokovic eliminated defending champ Andy Murray in straight sets and while fifth seed Roger Federer was sent crashing out of the ATP Tour's Miami Masters tournament in the quarter-finals on Wednesday.
Federer lost 3-6, 7-5, 6-4 to Japanese 20th seed Kei Nishikori who booked a semi-final showdown with former world number one Djokovic who defeated Murray 7-5, 6-3 on the hardcourts at Crandon Park.
"Kei did well to stay with me and not allow me to hold my serve," Federer said. "He was more consistent in the second and third set and those are the ones he won. At the end it's his credit."
Nishikori reached his second Masters semi and first in 2 1/2 years by winning the two hour, nine minute night match.
"I thought I really played well, especially in the third," Nishikori said. "I was hitting both deep and striking well. Everything was going well.
"There was couple of tough moments, but I was fighting through and happy to win today."
Nishikori next faces Djokovic, who is going for back-to-back Masters titles after his triumph at Indian Wells.
The 26-year-old Serbian Djokovic recovered from an early break in the second set to notch the victory in one hour and 29 minutes.
It was the first meeting between the two since Murray defeated Djokovic in the Wimbledon final.
"I tried to move him around, change the pace of the ball, mix it up with the slice, with different depth, angles and just stay tough out there," Djokovic said.
Djokovic hammered seven aces and broke Murray three times and is now 12-8 lifetime against Murray, including a 3-1 record in Miami.
The Serb settled into the match quickly and when he did lose his concentration he used his strong serve to rescue the points.
In the second set, Murray broke Djokovic in the fifth game to take a 3-2 lead. In the next game he double faulted twice and Djokovic went on to win four straight games to wrap up his ninth consecutive win.
Murray, who underwent back surgery on September 23, struggled for consistency sometimes on his backhand in the windy conditions. Other times he moved well enough to keep Djokovic on his back foot.
"I had many opportunities today like 30-all games and love/30s on his serve, and I didn't serve so well when I went ahead in the second set," said Murray.
"I would have liked to have done that better, but I was hitting the ball better from the back of the court. I was playing aggressive. I was taking the ball early. I was trying to come forward a bit. My game is not far from where I want it to be."
World number one Rafael Nadal booked his place in the quarter-finals of the Sony Open after thumping 14th seed Fabio Fognini in Miami.
Nadal, who is bidding for a maiden title in this competition, dropped just one game against the overmatched Denis Istomin in his last match and was equally impressive in a 6-2 6-2 victory over Fognini.
The 27-year-old Spaniard did not lose a single point on serve in the first set, with Fognini pushed to the limit by the top seed's powerful groundstrokes.
Fognini was well below his best and fell 4-0 down before stopping the rot in the fifth game, but the Italian could not impose himself on Nadal's serve and duly lost the first set before being immediately broken at the start of the second set.
Nadal, a runner-up in this tournament on three occasions, was rarely stretched thereafter and duly wrapped up victory inside 62 minutes against an opponent who made 35 unforced errors.
The 13-time grand slam champion will next face 12th seed Milos Raonic in the last eight, with the Canadian ending lucky loser Benjamin Becker's run in the competition with a 6-3 6-4 victory.
Second seed Novak Djokovic was also rarely troubled in a 6-3 7-5 win over Spain's Tommy Robredo and he will next face Andy Murray, who defeated Jo-Wilfried Tsonga 6-4 6-1, in a mouthwatering encounter.
Djokovic has an 11-8 lead in the head-to-head meetings with Murray but the Serbian will be champing at the bit for revenge after losing in the final of Wimbledon in 2013 when they last faced each other.
Meanwhile third and fourth seeds Stanislas Wawrinka and David Ferrer both exited the competition after suffering three-set losses.
Australian Open champion Stanislas Wawrinka battled back from losing the first set to Alexandr Dolgopolov to take the match to a decider, where the 22nd seed found his rhythm to seal a 6-4 3-6 6-1 victory.
Ferrer, meanwhile, lost a gruelling contest against Japanese 20th seed Kei Nishikori, who triumphed 7-6 (9/7) 2-6 7-6 (11/9).
Nishikori will meet Roger Federer next after the Swiss hammered Richard Gasquet 6-1 6-2, while Tomas Berdych set up a quarter-final tie against Dolgopolov with a 6-3 7-5 win over home favourite John Isner.
In the women's event, world number one Serena Williams cruised into the semi-finals by crushing fifth seed Angelique Kerber 6-2 6-2 in 62 minutes.
She will face Maria Sharapova in the last four after the Russian sealed a 7-5 6-1 victory over fellow former Wimbledon champion Petra Kvitova.
However, Sharapova must end a dreadful run against Williams in order to progress to the final of this competition for the fourth successive time, having lost her last 14 meetings with the American.
Top seed Rafael Nadal and reigning Aussie Open champ Stanislas Wawrinka posted straight-set victories in the third round at the WTA and ATP Miami Masters hardcourt tournament on Monday.
French Open champ Nadal needed just 59 minutes to rout Denis Istomin of Uzbekistan, 6-1, 6-0 while Wawrinka cruised into the fourth round with a 7-5, 6-4 dismantling of Edouard Roger-Vasselin of France at Crandon Park.
"I'm happy with the way I was fighting, the way I stayed positive in the game," said the 28-year-old Wawrinka. "Even if I was wasn't moving or playing so as well at the beginning, I stayed with him.
"I was fighting with myself to get control of the point."
Nadal, who has finished runner-up in this event on three occasions, will next face 14th-seeded Fabio Fognini, who battled back to beat Spaniard Roberto Bautista Agut 4-6, 6-3, 6-3.
Swiss Wawrinka will square off against Alexandr Dolgopolov after the 22nd-seeded Ukrainian rallied for a 3-6, 6-0, 7-6 (7/5) win over Dusan Lajovic.
Wawrinka has already won two titles this year, including claiming his first grand slam win in Melbourne in January. His best previous finish in Miami was a straight set loss to Nadal in the round of 16 in 2009.
Like Nadal, Canada's Milos Raonic barely broke a sweat on Monday.
Raonic, who dropped only five points on his serve in the match, reached the last 16 for the first time after being forced to withdraw from third-round matches with injuries the past two years.
"I just generally improved, especially on second serve returns (and) taking advantage more of those opportunities," Raonic said.
He next faces German Benjamin Becker, who beat Slovenia's Aljaz Bedene 6-3, 7-5.
"It's going to be a tough match but it's up to me," Raonic said. "I've got to play well. If I do, I can always give myself an opportunity to do well."
Seventh-seeded Tomas Berdych downed Portugal's Joao Sousa 6-2, 6-4, while 10th-seeded John Isner posted a 7-5, 6-3 victory over 18th-seeded Nicolas Almagro of Spain.
The American Isner will face Berdych in the next round.
On the women's side of the draw, world number one Serena Williams breezed into the quarter-finals while Russian fourth seed Maria Sharapova battled through three sets to advance.
Top-seeded defending champion Williams routed US qualifier Coco Vandeweghe 6-3, 6-1 in 78 minutes to book a last-eight matchup with German fifth seed Angelique Kerber.
Sharapova rallied to defeat Belgium's Kirsten Flipkens 3-6, 6-4, 6-1 after two hours and four minutes while Kerber took six minutes longer to eliminate Russia's Ekaterina Makarova 6-4, 1-6, 6-3.
Williams smashed 17 winners to only 11 unforced errors and denied her compatriot on all six of her break-point chances to book her 13th quarter-final in 14 Miami appearances.
"It was a much tougher match than the scoreline showed," Williams said.
Williams owns a 3-1 career edge over Kerber, whose lone win came two years ago on the Cincinnati hardcourts.
"I feel better than I did in my first few matches, though, so I hope I can keep going forward," Williams said.
Four-time grand slam champion Sharapova, a five-time Miami runner-up, is still seeking her first title at the hardcourt event.
"It's not like I didn't have my opportunities in those finals. I just didn't take them. That's why you come back and hope for another chance," Sharapova said.
The Russian made 10 double faults, half of them in the first set, and served no aces but improved as the match progressed and in the final set won five of 12 points off the Belgian's first serve and seven of nine off her second serves.
Next up for Sharapova will be Czech eighth seed Petra Kvitova who beat Serbian 12th seed Ana Ivanovic 3-6, 6-0, 6-0.
Dominika Cibulkova of Slovakia also advanced by beating Venus Williams 6-1, 5-7, 6-3.