MIAMI  - Britain's second-seeded Andy Murray mastered the tricky conditions to make short work of Australian Bernard Tomic on Saturday to reach the third round of the Miami ATP Masters and WTA Tournament. Tomic managed to win only 10 points in the final set of a 56-minute match dominated by the reigning Olympic and US Open champion, who has a training base in Miami. "It's very tough conditions," Murray said of his determination to get off to a quick start in his opening match after enjoying a first-round bye."You're never going to feel great your first match, especially when it's tricky conditions and with his game style, too," added the Scot.  "I don't know if he was tired or struggling with the humidity, but he was playing pretty low-percentage tennis. That played into my hands."World No. 3 Murray wasn't sure that Tomic deserved the jeers he heard from fans as he faded in the second set. "You know, it is tough when you're going behind and making quite a lot of mistakes," Murray said. "I have done it before when my head has gone down and you still want to win, but it doesn't always appear that way."Murray, who lost to top-ranked Novak Djokovic in last year's final, next faces Grigor Dimitrov, who won the first set against Simone Bolelli with the second set level at 1-1 when the Italian retired with a wrist injury. Murray, the 2009 Miami champion, beat the rising Bulgarian star to retain his title in Brisbane in January. The Scot remained perfect in two career matches against Tomic, the youngest player in the ATP top 100 at age 20. Murray broke in the fifth game and then held serve for a 4-2 lead, taking full advantage of 14 unforced errors in the first six games by Tomic.Tomic netted a backhand to give Murray a second break, and the first set, in the ninth game of the match. Murray broke Tomic twice in the second set as well, and closed it out with his eighth ace. In other men's matches, French sixth seed Jo-Wilfried Tsonga beat Serbia's Viktor Troicki 7-6 (8/6), 6-3 to reach the third round. World No. 1 Serena Williams continued her progress toward a sixth Miami WTA title with a 6-3, 6-3 third-round victory over Japan's Ayumi Morita.Serena Williams got off to a slow start, dropping her serve in the second game as Morita raced to a 3-0 lead. But the American bounced back with a vengeance, winning the next six games to pocket the first set.World No 1 Serena Williams was rolling Saturday, even before she got to her third-round match against Ayumi Morita at the Miami ATP Masters and WTA Hardcourt Tournament. The American, seeking a record sixth Miami WTA crown, resorted to some unfamiliar transportation -- a bicycle -- to beat the traffic into Key Biscayne and make her match. "The traffic was crazy and everyone was like, I have been here for an hour and I'm staying like eight minutes away," Williams said. "They were in the traffic for an hour. I'm like, 'OK, I'm not going to make my match if I don't get there.'"She asked hotel staff for a golf cart, but they didn't have one, offering a motor bike instead. "I'm like, 'I don't do motor bikes,'" Williams said. She was slightly less reluctant to try the bicycle, which she said turned out to be fun."It was probably one of my best memories I think ever, riding a bike to a match. That's pretty cool," said Williams, who was pleased to be told that tennis great Martina Navratilova sometimes rode a bike to Wimbledon. "Yeah?" Williams said. "Honestly, I hear a lot of players do that, but I never did that. So, check."Maybe the unfamiliar exercise accounted for her slow start against Japan's Morita, who broke Williams in the second game en route to a 3-0 lead. Williams was back on track soon enough, winning seven straight games to lock up the first set 6-3 and hold her serve in the opening game of the second.She gained the only advantage she needed with a break for 4-2 in the second. Serving for the match at 5-3, she gave herself a match point with her seventh ace and polished it off with a service winner. Despite how easily she turned the tables, Williams said she respected Morita's game."I get a good impression from her," Williams said. "I played her before. She's tough. She stays really focused and she stays really pumped up, which I think is a really good feature." Williams who currently shares the record of five Miami titles with German great Steffi Graf, next faces 13th-seeded Slovakian Dominika Cibulkova, a 6-3, 6-4 winner over Romina Oprandi. Two more top-10 women bowed out on Saturday, as Caroline Wozniacki and Petra Kvitova suffered third-round defeats. Young Spaniard Garbine Muguruza dispatched ninth-seeded Wozniacki -- a former world No. 1 -- 6-2, 6-4.Belgian Kirsten Flipkens beat seventh-seeded Kvitova -- a former Wimbledon champion -- 6-0, 4-6, 6-1. Defending champion Agnieszka Radwanska of Poland, the fourth seed, survived a scare en route to a 7-6 (7/5), 2-6, 6-3 victory over Slovakia's Magdalena Rybarikova. And fifth-seeded Li Na of China held on for a 6-2, 6-4 victory over American Varvara Lepchenko.