Australian Open 2018: What you missed on day four - Johanna Konta and Garbine Muguruza out as Novak Djokovic survives

Here is what you missed overnight on day four at the Australian Open...

Konta knocked out by 'lucky loser'

British interest in the women's draw was ended on the fourth day of the tournament as Johanna Konta suffered a shock defeat to 'lucky loser' Bernarda Pera.

Pera lost in the final round of qualifying only to be handed a place in the main draw when Margarita Gasparyan withdrew.

The Croatian-born American, ranked 123, has more than taken advantage of her spot and her first ever grand slam experience.

The 9th-seeded Konta had looked in good form in her first-round win over Madison Brengle but struggled to find her game against left-handed Pera and lost in straight sets 6-4, 7-5.

Konta wasn't too disconsolate following her earlier than expected exit. "It's a bit frustrating, but I'm still taking good stuff from this. I don't feel, by any means, it's a massive catastrophe. I play every event to be there until the end, so I definitely don't want to be going home this early," she said.

"But I think in terms of building myself back up again and then playing the way I want to play, I think I keep moving forward."

Djokovic stands the heat

The blazing Melbourne temperatures were a big talking point on day four, with the mercury nudging 40 degrees celsius on court. 

Novak Djokovic and Gael Monfils were both tested to their physical limits in a gruelling second-round match that Djokovic eventually won 4-6, 6-3, 6-1, 6-3. 

The Serb keeled over to get his breath back during the fourth set, while an exhausted Monfils was forced to leave the court and looked as though he might retire at the end of the third set. 

In the end it was Djokovic who managed to keep his composure, serving out the match against a revitalised opponent to complete the victory after 2hr 45min. After the match, Djokovic said of the conditions: "We both suffered on the court today. Really tough, brutal - especially for the first hour and a half. I was coming into the match knowing it was going to be a big challenge for both of us." 

Wimbledon champion Muguruza slayed by Hsieh

A second top-10 seed fell in the women's draw overnight as world No 3 Garbine Muguruza slipped to defeat against Hsieh Su-wei.

The Wimbledon champion recovered from 5-2 down in the first set to force a tie-break and rallied briefly in the second but tumbled to a 7-6,6-4 loss in the sweltering heat on Rod Laver Arena.

For 32-year-old Hsieh it was her second win against a player ranked in the top 20 in 17 years on tour - her other being that of Konta at last year's French Open.

Muguruza needed treatment early on for a blister on her foot and chalked up 43 unforced errors during the match. The 24-year-old's day was compounded when she received a warning from the match umpire for swiping a loose ball dangerously close to a line judge.

Kerber and Sharapova win to set up showdown

Angelique Kerber celebrated her 30th birthday with an emphatic 6-4, 6-1 win over Donna Vekic to set up a mouth-watering clash of former champions with Maria Sharapova.

Kerber, who won in Melbourne two years ago, is the form player in the women's draw and stretched her winning streak to seven matches with a controlled performance against Vekic.

The German ended a 27-tournament title drought with victory at the Sydney International and is one of the bookies' favourites to win a third major this fortnight.

Sharapova had earlier secured her place in the third round as she gained revenge over her US Open conqueror Anastasija Sevastova 6-1, 7-6.

The 2008 champion in Melbourne raced through the first set in 23 minutes and despite a slight wobble when serving for the match at 5-4, closed it out in the tie-break.

Sharapova was making her first return on Rod Laver Arena after serving her doping ban.

"I love Australia. I love the summertime. I was watching this tournament (last year) with a box of Kleenex next to me sick," she said.

"So, you know, I feel like I transported myself into the TV this year and I'm finding myself on Rod Laver Arena competing. A lot of things to smile about."

Thiem completes fightback against qualifier

Fifth seed Dominic Thiem survived his first career five-set match in Melbourne, rallying from two sets down to overcome qualifier Denis Kudla 6-7 (6), 3-6, 6-3, 6-2, 6-3.

Thiem lost both of his five-set matches in majors at Wimbledon and the US Open last year but came through today against the 190th-ranked American.

The 24-year-old sent down 21 aces and 57 winners in the match and was broken three times in the opening set.

After being broken once in the second, he then didn't face another break point for the rest of the match.

Match of the day

World No 8 Caroline Garcia's epic 6-7 (3), 6-2, 8-6 victory over Czech Marketa Vondrousova. The pair traded blows for two hours and 29 minutes on Hisense Arena.

Upset of the day

World No 3 Garbine Muguruza slumping to a straight-sets defeat to Hsieh Su-wei. The Wimbledon champion headed into the tournament with concerns over her fitness but was still fancied to go deep in Melbourne.

Quote of the day

"I don't think I've fallen over on my own two feet since I was going through growth spurts." Johanna Konta was at a loss to explain her frequent tumbles against Bernarda Pera. 

Stat of the day

41 - minutes it took American Madison Keys to thump Russia's Ekaterina Alexandrova, dropping just a single game.

Shot of the day

It's very rare you see Novak Djokovic so flummoxed by a shot that he doesn't move for it. This Gael Monfils backhand slice did just that however. 

Matches you don't want to miss tomorrow

Nick Kyrgios vs Jo-Wilfried Tsonga (first in the Rod Laver Arena evening session) has the feel of a heavyweight boxing match, and should be hugely entertaining. 

From a British perspective, the last player standing in either singles draw Kyle Edmund takes on Nikoloz Basilashvili just after 00.00 GMT on Court 2. 

Rafael Nadal meanwhile continues his bid for a 17th grand slam title, with a night match on Margaret Court Arena against Bosnian 28th seed Damir Dzumhur.