Novak Djokovic has made more history at Melbourne Park, achieving a feat only two others have done before.

The hope for an all-Australian duo to win the men's doubles title remains alive, while koalas inspired a head-turning outfit.

Here are five quick hits from day six at Melbourne Park.

1. Djokovic celebrates 100th Australian Open match with another win

Novak Djokovic extended his unbeaten run at Melbourne Park to 31 matches with a clinical straight-sets victory over Argentine 30th seed Tomas Martin Etcheverry.

The world number one needed two hours and 28 minutes to win 6-3, 6-3, 7-6 (7/2) at Rod Laver Arena.

But the match was historic for the Serb as the became just the third player to play 100 matches at the Australian Open.

He joins Roger Federer (117) and Serena Williams (105) as the only members of the century club.

"I think [this was] the best performance I had during this tournament," he says.

"I am pleased with the way I played through the entire match, particularly the first two sets."

Djokovic has won the Australian Open 10 times, winning 92 matches and losing just eight.

The Serb was asked about chalking up 100 matches at Melbourne Park, crediting his parents for the sacrifices they made to give him the opportunity to establish one of the greatest careers in the sport.

"Coming from Serbia during [the] 90s wasn't easy for my family,' he said.

"My parents endured a lot of adversity, economically and in every sense, in order for me to live my dream."

2. Players avoid handshakes over political tensions 

The fallout of political tensions and war were on display at Melbourne Park, with a pair of women's matches ending in a mutual wave, rather than a handshake.

Since Russia's invasion of Ukraine in February 2022, contests involving a Ukrainian player and a Russian or one from Belarus (an ally of Russia) haver been contentious.

On Friday, Belarusian and reigning women's champion Aryna Sabalenka defeated Ukraine's Lesia Tsurenko 6-0, 6-0.

At the end of the match the pair exchanged a wave, rather than a handshake at the net.

During her post-match interview on Rod Laver Arena, Sabalenka said she was "super happy" Tsurenko was "healthy and back at the top".

The two were set to go head-to-head at Indian Wells last year but the match did not eventuate. 

Tsurenko withdrew after suffering a panic attack when talking with officials about tennis's response to Russia's invasion of Ukraine, for which Belarus was used as a staging ground.

In June last year, Sabalenka said she did not support Russia's war in Ukraine.

At last year's French Open, Ukrainian Elina Svitolina refused to shake the Belarusian's hand after their match.

Similarly on Friday, Ukrainian Marta Kostyuk and Russian Elina Avanesyan didn't shake hands after Kostyuk triumphed 2-6, 6-4, 6-4.

3. Iconic Aussie animal inspires doubles fashion

While the action on court is the star attraction of every Australian Open, fashion has its place in the first grand slam of the year.

Clothing brands are keen to put the latest designs on their sponsored stars while some players show off their personalities, often becoming fan favourites.

Czech Adam Pavlásek and Uruguay's Ariel Behar turned heads at Melbourne Park on Friday in their first round men's doubles clash, donning matching shirts inspired by iconic Australian fauna.

The duo's koala-patterned shirt, with a pink backdrop and white collar, was certainly an attraction on Court 6.

It proved to be a winning choice with the duo advancing to the second round after beating Michael Venus and Jamie Murray 6-2, 6-4. 

They are no strangers to matching and standing out from the crowd.

The duo sported pink shirts featuring dogs wearing glasses at last year's US Open.

4. Men's Aussie doubles power through first round

Hopes of a third-straight local men's doubles title remain well and truly alive at Melbourne Park.

Back to their winning ways, reigning champions Rinky Hijikata and Jason Kubler charged into the second round of the Australian Open in a speedy 70 minutes.

The 16th seeds scored a comfortable 6-2, 6-4 victory against fellow countryman Chris O'Connell and his Serbian partner Laslo Djere.