Roger Federer held off local wildcard Ryan Harrison to set up a third-round clash against twice former Sony Ericsson Open champion Andy Roddick andSerena Williams served her way into the fourth round in Miami action on Saturday.
While men's number one Novak Djokovic and women's second-ranked Maria Sharapova progressed easily, former number one and twice Miami winner Kim Clijsters was eliminated at the Premier-level event.
Clijsters fought hard and survived six match points before falling to fellow BelgianYanina Wickmayer 6-4 7-6 in their third round clash.
"It was a special win for me today because she was one of my idols growing up," the 22-year-old Wickmayer said.
Australia's U.S. Open champion Samantha Stosur avoided an early exit by storming back after falling a set and 4-2 down to beat South African Chanelle Scheepers 2-6 7-5 6-2.
Federer, who has won 40 of 42 matches and six tournament titles since the 2011U.S. Open semi-finals, led his 19-year-old opponent 5-2 in the second set before Harrison extended him to a tiebreaker taken 7-3 by the Swiss for a hard-earned 6-2 7-6 win.
"I felt like I had to win the match like three times at the end, so I was relieved to come through," Federer told reporters after his second round tie.
"Beating an American in America is always a big deal, because this is where they usually play their very best."
Federer must next hurdle another homegrown foe in Roddick and although the Swiss world number three has mastered the American former world number one in 21 out of 23 matches, he does not expect it to be easy going.
"The head-to-head doesn't play a massive factor for me against Andy, because I know there's always a lot in Andy's racket depending on how he serves," said Federer."And if I don't play well, I know I won't win. So the pressure is there."
Roddick lost only nine points on serve and thundered down 10 aces to beatLuxembourg's Gilles Muller 6-3 6-2.
Djokovic prevailed over Marcos Baghdatis 6-4 6-4, subduing the Cypriot without the loss of a set for the first time in their last six meetings.
American Williams, the 10th seed, belted eight aces in an overpowering 6-2 6-1 rout of 21st seed Roberta Vinci of Italy.
"I played okay" said Williams. "I can definitely do better but I haven't played a lot."
Williams, whose five Miami triumphs tie her with Steffi Graf for the record, said she was still hungry for more.
"I need trophies," she said. "I want to add more and do more. There are records to break."
Second seed Sharapova advanced to the fourth round with a 6-4 6-2 win over American qualifier Sloane Stephens, while fourth-seeded Caroline Wozniacki beatCzech Petra Cetkovska 6-3 7-5.
Also coming through on Saturday was eighth-seeded Li Na of China, who won the last four games of each set to beat another Czech, Iveta Benesova, 7-5 6-2.
Men's fifth seed David Ferrer, another hot player on the men's tour with three titles this year, converted four of 10 break point opportunities to beat 19-year-old Australian Bernard Tomic 6-4 6-4.
