Venus Blasts Through to Semi-finals

Venus Williams sent an ominous warning to her Australian Open rivals after her quarter-final victory over Daniela Hantuchova this morning, by vowing to break her own record for the fastest ever serve by a woman.

The world number two blasted an ace timed at 128 miles per hour past Hantuchova to demolish the Slovakian 6-4, 6-3 this morning and reach the semi-finals.

Williams' booming serve was the fastest by any woman since 2001 and a mere two miles off her world record of 130mph, which she clocked at Zurich in 1998.

Williams said she surprised herself by her speed and vowed to have a crack at breaking her record.

"I haven't even tried to break my record," she said.

"Back when I was serving really big and I had the 205, I was always trying to serve really hard. I just tapered off, I forgot to serve faster.

"Nowadays, I just go for placement and, of course, power but when I hit that it just came out fast.

"Now I'm going to see if I can serve it even bigger than the record."

Williams struggled to find any rhythm on her serve, landing just 53% of her first serves, but when she got it right, she won a staggering 87% of points.

Her 128mph serve was eight miles faster than Andre Agassi's best effort in his 6-3, 6-2, 6-2 win over Sebastien Grosjean and equal to the Frenchman's hardest serve.

"I don't know if I served that well but did you see that one at 125?," she marvelled. "I thought 'wow' and I got a bit distracted by it and had to tell myself to refocus."

Williams' 75-minute win over seventh-seed Hantuchova was littered with mistakes, however, including 32 unforced errors, but the American was able to raise her game when she needed to ensure she beat her smaller, less experienced opponent.

Hantuchova did manage to break Williams' serve early in the first and second sets but conceded five breaks on her serve en route to defeat.

"I made a lot of errors but I think that Daniela didn't play her best," Williams reflected.

"It was my best match of the tournament but I'm my biggest critic, I'm always looking for things that I can do better after each match."

Williams, 22, has won Wimbledon and the US Open singles titles twice each and was runner-up at last year's French Open but has never graced the final at Melbourne Park.

She will play either Justine Henin-Hardenne or Virginia Ruano Pascual in Thursday's semi-finals.