Strugglers Serena, Sharapova survive at Miami
Serena Williams of the US returns the ball against Caroline Garcia of France during their match at the Sony Open, at Crandon Park Tennis Center in Key Biscayne, Florida, on March 22, 2014 - by Al Bello
Defending champion Williams and last year's runner-up Sharapova on Saturday struggled mightily to survive, with five-time finalist Maria Sharapova requiring nine match point to book her win.
Sharapova beat Czech Lucie Safarova 6-4, 6-7 (7/5), 6-2 in a battle which took five minutes short of three hours to complete.
Sharapova let out a scream of relief when she finally went through as Safarova's shot hit the net, Sharapova having missed two chances in the second set to wrap it up early.
"She was just hitting unbelievable shots on the match points," said Sharapova. "I kept asking myself how many more chances I had.
"I'm just so happy to go through."
Sharapova ended her marathon with nearly twice as many unforced errors, 51, as winners, 27, and double-faulted eight times.
Top seed Serena Williams waited out a 45-minute rain third-set interruption before dispatching France's Caroline Garcia 6-4, 4-6, 6-4.
World number one Rafael Nadal was set to play his opening match after a first-round bye later.
Serbian second seed and three-time Miami champion Novak Djokovic advanced to the fourth round when opponent Florian Mayer retired a day before their scheduled match with a groin injury. Djokovic will next play Tuesday.
Williams, 32, bidding for a record seventh title at her home tournament, now stands 63-7 at the venue and was far from pleased with her showing.
"Granted she played great, but I made so many errors, I hit so short," said Williams. "It really isn't the same player. I just have to do better.
"It's important to stay positive. Obviously I wasn't at my best. I had 40-something errors. It's not the way to play professional tennis."
Reigning Australian Open champion Stanislas Wawrinka downed Spain's Daniel Gimeno-Traver 6-0, 3-6, 6-3 to reach the men's third round.
The third-seeded Swiss raced through an 18-minute opening set, winning the first seven games before eventualy losing the second set.
Wawrinka recovered on cue in the third with an opening break to advance in just under 90 minutes and then admitted he is still adjusting to his new status as a Grand Slam winner.
"I still have some ups and downs mentally. I was negative in the second set a little bit stupidly, but then I'm really happy with the way I started the third set," Wawrinka said.
"I'm happy to win. That's the most important. It was the first one here. It's never easy. Conditions were really slow, really humid. You need to get through. That's it -- just win the matches."
Wawrinka, 14-1 this year, fired eight aces and broke four times in only his fourth ATP match since beating Rafael Nadal to capture his first major title.
Czech seventh seed Tomas Berdych began with a 7-6 (7/5), 6-1 win over Frenchman Stephane Robert while 10th seed John Isner defeated Donald Young 6-7 (5/7), 6-3, 6-4.
Canadian number 12 Milos Raonic put out Jack Sock 6-4, 7-6 (7/1) and Italian 14th seed Fabio Fognini stopped Lukas Lacko 6-4, 6-4.
German Tommy Haas, a 2013 semi-finalist, was forced out before his first match with a recurring shoulder injury.
Wimbledon finalist Sabine Lisicki, seeded 14th, was unable to play due to influenza, handing a walkover to Belgian Kirsten Flipkens.
German fifth seed Angelique Kerber beat Tsvetana Pironkova 6-0, 6-2, eighth seed Petra Kvitova stopped Croatian Donna Vekic 6-3, 6-4 and Ekaterina Makarova upset Italian ninth seed Sara Errani 6-3, 2-6, 6-4.