Zhang was too often tentative from the baseline and Konta capitalised, dipping in a well-placed lob to lead 3-1 and then unleashing a thundering backhand return for 5-2 and the double break.
Victory in Saturday’s final against either seventh seed Angelique Kerber or unseeded Briton Johanna Konta, would give her a 22nd grand slam title, moving her to a tie with Steffi Graf for the most in the Open era.
Williams is the overwhelming favourite, and not just based on recent form.
“I definitely block it out”, Williams said in reply to a question about equaling Graf’s mark.
Konta broke back to get on the board and the match at last took on the feel of a genuine contest.
But Konta’s success is enough to inspire a new generation of girls to take up the sport.
Johanna Konta’s superb Australian Open run – in which the 24-year-old became the first British woman for 33 years to play in a Grand Slam semi-final – came to an end with defeat by German Angelique Kerber this morning.
“I needed time off just to take a minute and just chill and re-heal, get ready”, she said after the 64-minute battering of the Pole.
But what a debut Konta has had, the first British woman to reach the semi-finals here since Jo Durie in 1984.
Kerber will face 21-time Grand Slam victor Williams in Saturday’s final.
Graf was the last German player to win the women’s title in Australia, in 1994, and Kerber is asking for some advice. “When I was serving, everything is just coming back to your side with that power, so deep that you can not do anything”.
Williams cleaned up the first set in just 20 minutes before Radwanska elicited the largest cheer of the match at that time when she held serve in the first game of the second set, avoiding an embarrassing potential “double bagel” 6-0 6-0 score.
For Konta it is a well earned rest and a trip home – that’s Eastbourne, and not some Sydney suburb – and she is still planning on playing Fed Cup for Great Britain in their latest zonal challenge, assuming physically her body holds up. “It blows my mind right now”, Williams said in a courtside interview. “I still have to win two matches against potentially two extremely tough opponents”, she said.
The second set was closer, with Radwanska holding serve three times and breaking Serena’s powerful serve once. But the 34-year-old Williams lifted again to finish it off, winning the last eight points of the match and closing with three aces and a big forehand victor.
Konta claimed she did not wobble as she served for the first set when leading Zhang 5-2. I’m really looking forward to the chance of playing her again soon.
That loss in NY has obviously resonated in her preparations for Melbourne Park, where she has appeared completely focussed since a testing first round clash with Italy’s Camila Giorgi.
With the first set under her belt, Kerber came out for the second set aggressively, hitting hard to grab an early break and pile the pressure on Konta.
Radwanska, ranked fourth in the world, is no stranger to the top level of women’s tennis but she was made to look a minnow by Williams, who looks ominously back to her very best.
“I never would have been here in Melbourne sharing the facilities with guys who were my idols growing up, Andy Murray and Roger Federer, guys like that”.