The break points just keep on coming in this quarter-final, but this time Kalinskaya manages to save two to reach deuce as she aims to avoid losing serve for a third time.

The world number 75 sticks with Zheng in a baseline exchange and it's the 12th seed who misses first.

Image source, Getty Images

Britain's Lucy Shuker has lost in the first match of the women's wheelchair doubles which means the 43-year-old's Australian Open is over.

Shuker and French partner Pauline Deroulede were defeated 7-5 7-6 (7-2) on court eight by Columbian-Chinese team Angelica Bernal and Zhenzhen Zhu in the quarterfinals.

On Tuesday, Shuker was knocked out in the first round of the women's wheelchair singles by top seed Diede de Groot. The Dutch 27-year-old has won 37 Grand Slam titles, including 20 singles majors.

Kalinskaya reads a serve and whips a backhand cross court for two break points.

Zheng can't rescue the situation, instead missing a forehand and once again Kalinskaya breaks back immediately.

Zheng, as the last seeded player left in this half of the draw, is favourite here - but that probably counts for very little given the high-profile shock exits we have already seen to this point.

She already knows she has a scrap on her hands today.

Having broken Kalinskaya for a second time, the 12th seed finds herself 0-30 behind on serve.

Kalinskaya is struggling to live with the improving Zheng and a couple of misses bring her quickly back under pressure.

Zheng has reduced her errors and creates two more break points, but only one is required!

A couple of clean backhands help Zheng get up and running on serve and a confidence-boosting hold is secured with an ace.

Both players appear to have quickly shaken off the early nerves that appeared to hamper them in the opening couple of games.

Image source, EPA

Britons Alfie Hewett and Gordon Reid continued their Australian Open campaigns with wins in both the wheelchair singles and doubles.

Top seed Hewett beat unseeded Chilean Alexander Cataldo 6-0 6-2 in the wheelchair singles quarter-finals on court six. The eight-time Grand Slam champion will face Belgium's Joachim Gerard in the semi-finals.

Former Australian Open champion Reid also reached the final four. The fourth seed beat Dutchman Tom Egberink 7-5 6-2 on court five. Two-time Grand Slam champion Tokito Oda of Japan, 17, will face Reid for a place in the final.

Four-time wheelchair doubles defending champions Hewett and Reid also won in the first match of their Australian Open title defence.

They beat Australian pairing Anderson Parker and Ben Weekes 6-1 6-0 in the quarter-finals on Kia Arena and the British pair will face Japanese duo Daisuke Arai and Takashi Sanada for a spot in the final.

Kalinskaya, settling into this now, takes charge on serve with a forehand winner before a powerful groundstroke proves too much for Zheng to handle as she scrambles across the baseline.

Britain's Neal Skupski and American Desirae Krawczyk are now serving for a place in the mixed doubles final and hold a 5-1 second set lead against Australian pairing Olivia Gadecki and Marc Polmans.

Zheng misses again and we have back-to-back breaks at the start of this quarter-final!

That will do Kalinskaya a world of good after losing the opener. Game on...

Zheng's positive start continues as the 12th seed moves to 30-0 on her opening service game, but a missed forehand brings Kalinskaya level and offers hope of an immediate response.

Into the net from Zheng. Kalinskaya has a break back point.

Jonathan Jurejko
BBC Sport in Melbourne

Quite the array of Australian sporting royalty on Rod Laver Arena before the players emerged for the night session.

That's because we have just seen former world number one Lleyton Hewitt - one of Melbourne's own - be inducted into the Australian Tennis Hall of Fame.

In 2001, a 20-year-old Hewitt became the youngest player to hold the world number one singles ranking, before going on to claim Grand Slam triumphs at the US Open in 2001 and Wimbledon 2002.

A bronze bust of Hewitt, which will sit alongside ones of the other greats, in Melbourne Park is also revealed.

Laver watches on in the house bearing his name, as does 24-time major champion Margaret Court.

The other famous face there - certainly to 90s UK soap fans - is Hayley from Home and Away. That, of course, is Bec Hewitt - Rusty's other half.

Image source, Getty Images

Ah, a tough start for Anna Kalinskaya.

Zheng Qinwen wastes no time putting pressure on her opponent in the opening game.

The Russian misses a forehand to concede a first break point but saves it superbly with an angled forehand.

But successive double faults hand Zheng the early advantage.

Anna Kalinskaya had never won a main-draw match at the Australian Open in four previous attempts.

Yet the 25-year-old could reach her first Grand Slam semi-final today.

Zheng Qinwen, at just 21 years old, is hoping to emulate compatriot Li Na's Australian Open triumph in 2014 - but first she must reach her first major semi-final.

Ready? Kalinskaya will serve first in the last of the women's quarter-finals.

Britain's Neal Skupski and American Desirae Krawczyk are now a set and a break up in their mixed doubles semi-final against Australian duo Olivia Gadecki and Marc Polmans.

On Gadecki's serve, Skupski and Krawczyk were unable to convert two break-points, but then win the game and are three holds of serve away from moving into the Australian Open final for the first time as a pairing.

Daniel Kiernan
Former British tennis player

It's incredible. My last ever singles match as a player was against Rohan Bopanna in 2005. That was almost 19 years ago. For him to just even still be swinging a tennis racquet above his head is pretty impressive.

He's mastered the game, he's world number one and no-one can ever take that away from him. It's a real feel-good story because Rohan is a delight. Everybody loves Rohan and he's got time for everybody.

Image source, Getty Images

"Indian tennis and India needed this. We don't really have many tennis players coming up. I think it's just going to inspire a lot of people. I don't think just in tennis but also people all over the world being 40 and above. I just think it's going to inspire them in a different way."

You can read more about Rohan Bopanna becoming the oldest men's doubles world number one in history here.

The pairing of Britain's Neal Skupski and American Desirae Krawczyk took the opening set in their mixed doubles semi-final against Australian duo Olivia Gadecki and Marc Polmans.

In the early stages of the second set we're still on serve.

Skupski and Krawczyk are aiming for their third Grand Slam title together after twice winning the mixed doubles at Wimbledon.

The top half of the Australian Open women's singles draw has been blown open by a series of shock exits and is guaranteed to lead to a finalist very few would have predicted.

Earlier, Ukraine's Dayana Yastremska defeated Czech teenager Linda Noskova to reach the semi-finals.

She will face either China's Zheng Qinwen or Russia's Anna Kalinskaya.

World number 15 Zheng reached her first major quarter-final at last year's US Open, while the 75th-ranked Kalinskaya had never won three matches at a single Grand Slam before this year's Australian Open.

A massive opportunity for both today on Rod Laver Arena. Who can seize it?

Image source, Getty Images

Image source, Getty Images