d-ucator: Can't quite work this match out yet...glimpses of brilliance with some ugly bits thrown in. So much on the line.

Will the real Serena please stand up? Here she is. Venus leaves the door open for her little sister with a double fault for 30-30, Serena running inside and locking the door behind her.

A sumptuous, backhand volley spins out of Venus' reach to tee up the break point, a booming backhand sealing it.

Image source, Getty Images

Serena needs a big service game and she needs it quick. The 22-time Slam champion starts slowly, going 0-30 behind before roaring back. A serve out wide cannot be returned successfully by Venus, darting across court and into the far tramlines, and Serena finally holds serve. Fiance Alexis Ohanian nods his encouragement.

Image source, EPA

Jill Craybas
Former world number 39 on BBC Radio 5 live sports extra

Venus is starting to settle a little earlier in the match than Serena. Serena looked a little tentative on her ground strokes in that point.

Image source, Getty Images

Will this game finally produce a hold of serve? Will we ever see a hold of serve again? Yes!

Venus is the more fluent of the Williams sisters, constructing some wonderful points to earn the first hold of the match.

Serena puffs out her cheeks as she wanders to her chair. Not found her rhythm yet.

Image source, EPA

The Venus head scratch is back when Serena moves 40-30 ahead, only to see her sister melt quicker than a lump of mature cheddar in a 200C oven. Extraordinary.

TWO double faults give Venus a break point, which is quickly wiped out by another Serena ace, but then the younger Williams inexplicably double faults again to hand over the game.

Four games, four breaks...

* denotes next serve

Image source, Reuters

Laver settles down as the players walk back onto court from the changeover. Murmurings of bemusment/excitement humming in the air.

Venus scratches her head as she plants a forehand volley into the net for 15-0, she can't do anything about Serena's next offering - a thunderbolt of an ace down the 'T'.

Venus smacks a baseline forehand at Serena's feet, adding a crackerjack of a backhand to level at 30-30...

Image source, AFP

Jill Craybas
Former world number 39 on BBC Radio 5 live sports extra

I was surprised she got so frustrated. That's an amazing reaction so early in the match. It shows you mentally where she is at this point.

Image source, AFP

Now, now. Serena shows signs of the pressure in her mind when she loses the first point, smashing her racquet into Laver's blue acrylic. Head gone, racquet gone. New strings please...

Serena channels her frustration into the next point, hammering home a thunderous forehand. Another second break point goes begging when Venus responds with one of her own - but not the third. Venus meekly slaps a forehand into the net and this break-fest continues.

Image source, AFP

More ooohs and aahhs than Bonfire Night at your local scout hut. Another fierce rally gets the Melbourne crowd excited as does Serena racking up another break point. Venus ploughs a first serve down the middle, moving into the net to volley home. Deuce...

Image source, AFP

Well, well, well. We wanted a Hollywood blockbuster - and we've had a hell of an opening scene. Not quite Trainspotting, but it's up there. Break point for Venus. And she gets it! Venus goes toe-to-toe with her younger sibling, who overcooks a return. Two games, two breaks, all square.

Image source, AFP

Serena's probably the greatest server the women's game has ever seen. She's not going to let her sister back in straight away. Is she? Possibly. Venus has hope at 30-30, hope extinguished by a blistering ace out wide from Serena. Down the middle with the next serve, baseline battle commences. Serena goes wide! Deuce...

This was not how Venus dreamt it. A couple of rogue backhands give Serena early hope at 0-30, although a 179kph ace gets Venus on the board. 

However, two rasping returns - one from either side of the court - leaves Venus wafting at Melbourne air. 

The hot favourite is already ahead...

Image source, AFP

Jill Craybas
Former world number 39 on BBC Radio 5 live sports extra

In the locker room, they were eating together and chilling with each other. In my mind it would be weird if they didn't do that. Even though they were very relaxed before the match, when they were walking out in the tunnel, both of them became very professional and very focused. 

Image source, AFP

Here we go then. Venus is back, Serena stands up, both sisters are ready, Venus to serve first....

Mind games? Venus saunters off court after the knock up, possibly visiting the ladies' - although I couldn't - and wouldn't - like to say. Serena has a couple of minutes of deep thought...

Image source, Getty Images

BBC Radio 5 live

BBC 5 live's commentary of today's final has just kicked off. You can listen in using the player at the top of the page.

Our team of Russell Fuller, Gigi Slamon and former Tour player Jill Craybas are sat in position in Laver, providing all the details/analysis over the next hour or two.

There will also be highlights of today's game on BBC Two from 13:00.

While the odds are stacked heavily in Serena's favour, older sibling Venus isn't planning to roll over.

Venus isn't a bad player you know. Eight Grand Slam trophies, 49 tour titles, over £27m of prize money...

"When I'm playing on the court with her, I think I'm playing the best competitor in the game. I don't think I'm chump change either, you know," she said.

"I can compete against any odds. No matter what, I get out there and I compete."

The two players are knocking up on Laver, the arrival of each bringing more cheers and shrieks than you'd hear at a Bieber concert.

The pair barely looked at each other as they walked from locker room to court, but apparently had breakfast together this morning. Wonder what they chatted about? The weather, love lives...tennis?

Image source, EPA

Some family members quibble over inconsequential rivalries. Like who cooks the best apple crumble. Not the Williams's. Even the two sisters fighting for Grand Slam tennis titles has not put any distance between them.

"Nothing can break our family," says Serena. "If anything, this will definitely bring us closer together, knowing that I want to see her do the best that she can possibly do.

"I know that she definitely wants to see me do the best that I can do. This is a story. This is something that I couldn't write a better ending for.

"It's the one time that I really genuinely feel like no matter what happens, I can't lose, she can't lose. It's going to be a great situation."