Miami Masters PHOTOS: Serena, Nadal brush off bomb scare to cruise through

Defending champion Serena Williams closed in on a seventh Sony Open title with a 6-2, 6-2 quarter-final demolition of German Angelique Kerber on Tuesday, a win that came as the Crandon Park tennis facility was locked down due to a bomb scare.

Williams' win sets up a semi-final rematch of last year's final against Maria Sharapova, a five-time runnerup on the Miami hardcourts, who advanced with an equally impressive 7-5, 6-1 win over eighth-seeded Czech Petra Kvitova.

While Williams was shutting down fifth seed Kerber, Miami Dade police were locking down the sprawling tennis complex after a suspicious package was found at the main entrance.

Four lane traffic was halted in both directions in front of the complex while spectators were prevented from entering or leaving the facility.

"Yeah, there was a bomb threat and a lockdown but that's all I know about it. Scary," said Williams.

Sharapova and Williams, who have both achieved a career grand slam and held the number one ranking, were expected to develop into one of the great rivalries in women's tennis.

But it has not quite worked out that way with Williams dominating the series, winning 15-of-17 career meetings including the last 14.

The pair have clashed three times in Miami, Williams winning all three.

"It's no secret that she's been a big challenge of mine, an opponent that obviously I would love to beat," said Sharapova, who has not beaten Williams in almost a decade.

"There are certainly ways that I need to step up in certain situations that I haven't been able to do in the past against her.

"But it's great that I have come to that stage and have the opportunity to play her again."

Certainly Sharapova will have to be at her best as Williams' title defence has picked up steam with each match.

The World No 1 needed just 62 minutes to dispose of Kerber and has dropped one set on route to the final four.

"When you're playing champions, you have to play your best," said Williams, looking ahead to her meeting with Sharapova. "She always plays her best and her heart out against me.

"We just have to bring the best because we both are really good players. We just both do the best we can when we try to play each other.

"I love playing her. I really do."

Sharapova, who has come up short in the Miami final each of the last three years, dropped her opening serve to Kvitova but that would be the only time in the entire match.

The fourth-seeded Russian took control with a break to get back on level terms at 4-4 and then again to close out the first set. Sharapova then dominated the second set, storming through the first five games before a reeling Kvitova held her serve.

"I didn't have a good first few games, so I was happy that I was steady, that I kept trying to do the right thing, kept trying to be aggressive," said Sharapova. "I think that paid off as the match went on because I made a few too many unforced errors in the beginning."

Unruffled by a bomb scare that locked down the Sony Open late on Tuesday, World No 1 Rafael Nadal brushed past Italy's Fabio Fognini 6-2, 6-2 to join Novak Djokovic, Roger Federer and Andy Murray in the last eight.

Officials announced a suspicious package had been left near the main entrance to the sprawling tennis facility which was quickly locked down, keeping thousands of spectators from entering or leaving while Miami Dade police investigated.

The all clear was given just before Nadal stepped onto the CrandonPark centre court to face Fognini in the final match of the night.

The Spaniard showed no signs of being alarmed by the bomb scare as he completed the win in 62 minutes.

Nadal's great rival Federer was also in cruise control, needing just 49 minutes to dismiss ninth seeded Frenchman Richard Gasquet 6-1, 6-2.

"Look, things went well out on the court today," said the Swiss 17-time Grand Slam winner. "You just take what you get and you run with it.

"I think I played well. I served well. I made my returns I had to and stayed aggressive, so I didn't let him just make errors.

"I forced him to do stuff. It was a good match for me."

Defending champion Murray, playing his first event since splitting with coach Ivan Lendl last week, has looked increasingly comfortable and confident on his own.

He disposed of 11th-seeded Frenchman Jo-Wilfried Tsonga 6-4, 6-1 without facing a single break point.

Murray, fighting for form after undergoing off-season back surgery and going solo after ending his successful partnership with Lendl, finally seemed to put some of the distractions behind him, although he requested pain relief tablets for his back during the first set.

"We played each other a lot obviously," said Murray looking ahead to Wednesday's quarter-final. "We have played each other here three times, I don't know, maybe four times.

"You know, the conditions can change a lot here. Obviously it can be extremely windy or very hot and humid.

"Ultimately whoever deals with those things better on the day and whoever plays better will win.

"Whether I beat him the last time or he beat me the last three or four times, I don't think it matters too much."

Djokovic, a three-time winner on the Miami hardcourts, had only two break points the entire match but that was all the second seeded Serb needed, converting both chances on his way to a 6-3, 7-5 win over Spaniard Tommy Robredo.

While the day got off to a gloomy start with early morning showers delaying play by 30 minutes, tennis fans were treated to a lineup of sparkling action with nine of the world's top 10 men battling for spots in the quarters.

Djokovic, riding the momentum from his Masters Series win in Indian Wells nine days ago, was first through to the last eight and was soon followed by Murray, setting up rematch of last year's Wimbledon final won by the Briton.

It was just the second match of the tournament for Djokovic, who received an opening-round bye and advanced to the last 16 on a walkover when Florian Mayer withdrew with a groin injury.

"Very solid win," said Djokovic. "I just was telling myself to stay mentally tough out there and composed and not get carried away by few points.

"I have done well. I have served well. I made him play an extra shot in important moments and that's why I'm satisfied with the overall match today."

Not everything at CrandonPark tennis center went according to script, however, as Japan's Kei Nishikori and Ukraine's Alexandr Dolgopolov pulled off a pair of fourth-round upsets.

Dolgopolov battled to a 6-4, 3-6, 6-1 win over Swiss third seed and Australian Open champion Stanislas Wawrinka, while Nishikori shocked fourth seeded Spaniard David Ferrer 7-6(7), 2-6, 7-6(9).

In other fourth-round action, big-hitting Canadian Milos Raonic blasted German lucky loser Benjamin Becker 6-3, 6-4, while another big-hitter, towering American John Isner, was beaten 6-3, 7-5 by Czech seventh seed Tomas Berdych.