By Sophie Brown
BBC Sport at Wimbledon
Third seed Jelena Jankovic had a scare before seeing off Czech player Lucie Safarova 5-7 7-6 6-2 in a thrilling third-round match at Wimbledon.
Jankovic shows her frustration during the Court One marathon
After trading breaks of serve, Safarova, 20, snatched the first set.
Serb Jankovic levelled on a tie-break after a marathon 75-minute second set but a rain delay seemed to unnerve Safarova and Jankovic prevailed.
Serena Williams and Justine Henin were easy winners on Friday, but Martina Hingis went out to Laura Granville.
Jankovic said after her match: "It was a big battle out there and at one point I was thinking 'is there any way out?'
"But I managed to win the second set somehow. I was fighting. I was staying strong and that was the difference."
Williams ignored the frustration of a lengthy wait to get on court by hammering Milagros Sequera 6-1 6-0.
The pair had to wait for 215 minutes while Janko Tipsarevic beat Fernando Gonzalez in five sets.
And Williams ensured no more time would be wasted once on Centre Court by winning the first set in 22 minutes.
I'm feeling pretty good all round. I played really well, I'm feeling really positive and like I'm going to get there
The seventh seed played some great tennis while an overawed Sequera, in round three for the first time, made a string of errors as she slid to defeat.
Williams said: "I'm feeling pretty good all round. I played really well, I'm feeling really positive. I'm feeling like I'm going to get there.
"My hamstring injury is a lot better - which I'm really excited about. It's the first time it's felt this good."
On playing Daniela Hantuchova next, Williams added: "It will definitely be tough."
Top seed Henin also wasted little time in booking her fourth-round spot.
The Belgian, aiming to win the only Grand Slam to so far elude her, beat Elena Vesnina 6-1 6-3 on Court Two.
Henin raced through the first set in just 21 minutes and returned after an hour's rain delay to finish off the Russian, who is ranked 67 in the world.
The 25-year-old now meets 15th seed Patty Schnyder, who saw off Alona Bondarenko after a three-set tussle.
"I'm very happy with the way I played today - very aggessive, very consistent," said Henin, who is yet to drop a set at this year's Championships.
"It's been good for me this week. I've had pretty easy matches."
In contrast, her next opponent Schnyder had to work hard to see off Ukrainian Bondarenko.
The pair split the first two sets before the Swiss left-hander finally came through for a 6-4 3-6 8-6 victory against the 24th seed.
Former champion Hingis went out in the third round for the second year in a row as she lost 6-4 6-2 to Laura Granville on the notorious Court Two.
Hingis looked ill at ease and appeared to be struggling with injury as unseeded Granville dominated the first set with her serve.
Hingis won her only Wimbledon title 10 years ago
Granville broke at the start of the second set and Hingis failed to convert any of four break points at 3-2 down.
That was her last chance and Granville quickly wrapped up a famous victory.
Hingis, who has been suffering with a hip injury, said she probably should have missed this year's Championships.
"I think overall I shouldn't have played so I see this as a success getting through two rounds," she said.
"I wish I'd done better but at the end of the day I'm happy I'm getting healthier again and that's the most important thing.
"I had to miss out on the French Open and I just didn't want to miss Wimbledon. At the end of the day it probably wasn't the smartest thing but at least I gave myself a chance."
There was a shock on Court 13, where 31st seed Michaella Krajicek, who thrashed Britain's Katie O'Brien in the previous round, beat eighth seed Anna Chakvetadze in a marathon three-set battle.
Dutch player Krajicek, half-sister of 1996 men's singles champion Richard, finally came through 7-6 (10-8) 6-7 (5-7) 6-2 against the Russian.