Andre Agassi relied on brains while Venus Williams leant heavily on brawn as the two Americans took strides into the semi-finals of the Australian Open on Tuesday.

Williams overpowered the slightly-built Daniela Hantuchova for a 6-4, 6-3 victory -- at one point threatening her own speed service record -- as Agassi wove a web of intricate tactics to confound Frenchman Sebastien Grosjean.

"It was one of those matches where I felt pleased with the manner in which the match was being played," Agassi smiled, ever the euphemist.

What he could easily have said was that he blunted every Grosjean weapon, stifled every Grosjean hope and forced the 12th seed to dance to his rhythm throughout the 6-3, 6-2, 6-2 win.

"Every tournament he plays he can win," a subdued Grosjean conceded afterwards. "He is playing so well."

Chasing a fourth men's singles crown here, a record for an overseas player, Agassi played every point to perfection, directing rallies throughout and bamboozling Grosjean for two mesmerising hours.

"I just felt very solid on my groundstrokes, serving well, hitting forehands and backhands well... There was a lot out there I have got to be happy about," he said.

COOL CHANGE

Seeded second, Agassi has not lost here for 19 consecutive matches. The champion here in 2000 and 2001 was unable to defend last year, pulling out on the eve of the event with a wrist injury, but looks in great shape to snatch back the trophy.

Grosjean sweated and toiled even though a cool breeze relieved Melbourne Park from the scorching temperatures which had caused a suspension of play just 24 hours earlier.

The locals call it a "cool change" -- that Melbourne phenomenon where erratic temperature swings of up to 20 degrees Celsius from one day to the next are the norm.

But there was no relief for Grosjean as Agassi turned the screw on centre court.

Pounding away from the baseline, Agassi sent the Frenchman scampering to and fro, leaving him gasping for air in the shade at the back of the court.

In each of the three sets the Frenchman cracked, dropping serve when Agassi cranked up the heat. Agassi, just a few months shy of his 33rd birthday, did not drop serve once.

"Today was tougher than the scoreline, it was toe-to-toe," Agassi said afterwards. "But I was pleased with the way I was playing... felt great about putting it away."

Next up for the winner of seven grand slam crowns is South African Wayne Ferreira, who beat Spain's Juan Carlos Ferrero.

Ferreira, last in a grand slam semi-final 11 years ago when he lost to Stefan Edberg in Melbourne, was inspired as he hustled out the fourth-seeded Spaniard 7-6, 7-6, 6-1.

Only a couple of vowels separated the pair's names on the scoreboard but they were streets apart in terms of temperament on the big points, Ferrero flailing wildly at key moments while Ferreira kept his cool.

"There has been a great change over the last year," the 31-year-old South African said, moments after stepping off court. "I have become mature in the way I play the game. Mentally I am much better now."

Ferreira can only hope his new-found maturity is enough against Agassi -- his elder by a year.

The pair have played 10 times, Agassi winning on each occasion and Ferreira claiming just a solitary set.

"Yeah, he has a certain game that brings out the worst in me," Ferreira grinned, "But right now I feel so great I have nothing to lose."

FLEXED MUSCLES

While Agassi was all guile and artistry, Venus flexed her muscles to bounce Hantuchova out of the quarters.

Her 75-minute win over the seventh seed was littered with mistakes, including a whopping 32 unforced errors, but the American raised her game when she needed to.

She struggled to find a rhythm on her serve, landing just 53 per cent of her first deliveries, but when she got it right, she won 87 percent of points.

Her 201 kph serve -- just four kph slower than her own record set in 1998 -- was 12 kph faster than Agassi's best effort against 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 201?," Williams grinned. "I thought 'wow' and I got a bit distracted by it and had to tell myself to re-focus."

Re-focus she did and closed out to move a step closer to a first Australian Open crown.

Champion at both Wimbledon and the U.S. Open in 2000 and 2001, she will next face either Justine Henin-Hardenne or Virginia Ruano Pascual who were playing later on Tuesday.