By Greg Stutchbury
MELBOURNE (Reuters) - A scintillating fireworks show that illuminated the cityscape and commemorated Australia Day fittingly capped an explosive performance by Venus Williams and the Stars and Stripes brigade at the Australian Open on Monday.
The fireworks display, which has disrupted play previously at Rod Laver Arena, began minutes after Venus advanced to her first grand slam quarter-final since the 2010 U.S. Open with an upset win over sixth seed Agnieszka Radwanska.
The 34-year-old's victory ensured three American women would be in the last eight of a grand slam for the first time since the 2004 U.S. Open as she joined younger sister Serena and teenager Madison Keys.
Men's top seed Novak Djokovic also moved up a gear to beat Luxembourg's Gilles Muller and next faces Milos Raonic, who became the first Canadian male since Robert Powell in 1912 to reach a third career grand slam quarter-final.
"Not having played Gilles before was tricky coming in," Djokovic said in a courtside interview. "I did find it uncomfortable at times but I found a way through."
U.S. Open finalist Kei Nishikori's quest to become the first Asian male to win a grand slam advanced with a clinical victory over Spanish ninth seed David Ferrer.
"I was feeling a lot of confidence (because) I had nothing to lose so I played almost 100 percent tennis," said the Japanese.
Nishikori will meet defending champion Stan Wawrinka in the quarter-finals after the Swiss exacted some 2014 French Open revenge with a four-set victory over Guillermo Garcia-Lopez.
That French Open victory by the Spaniard ensured Wawrinka became the first Australian Open champion to lose in the first round at Roland Garros since Petr Korda in 1998.
TOUGH WIN
Serena also avenged an early loss at the 2014 French Open to Garbine Muguruza with a tough three-set victory over the hard-hitting Spaniard.
The American was justifiably nervous, having failed to advance further than the quarter-finals in her last three Australian Opens as she self-destructed against lower-ranked opponents.
After they shared the first two sets Williams, battling a cold, somehow managed to hold off six break points in her first service game of the decider and eventually ended the 21-year-old's resistance.
"I had to play the best match of the tournament or else I was going to be out," Serena said. "When I have to go up a level, I have to. I can't afford to stay at the same level or I will be where I was at the French Open."
Williams will meet last year's beaten finalist Dominika Cibulkova who outslugged twice champion Victoria Azarenka.
It was the Belarusian's earliest exit at Melbourne Park since she lost at the same stage in 2011 to China's Li Na, though after an injury-plagued 2014 the unseeded 25-year-old was pleased with her progress on her comeback.
"I think there are a lot of positive things to take from here. It's a good start," she said.
Azarenka's exit passed the mantle of the most dangerous outsider to watch to 19-year-old power-hitting Keys who is coached by former world number one Lindsay Davenport.
Keys, who destroyed twice Wimbledon champion Petra Kvitova in the third round, was equally as destructive in her 6-2 6-4 win over compatriot Madison Brengle as she set up a clash against Venus.
"I haven't been in this situation before," said Keys. "I'm going to make the most of it but, at the same time, no matter what I'm not really going to be satisfied with any win.
"I want to be at the end of the tournament holding the trophy up. That's my goal in the long run."