Another big max from Heta but the 17-year-old replies with a 140 as he gets to a finish first.

And he takes out 60 again exactly the same way - double top and double 10!

A 140 to start the leg from Damon Heta and he follows up with a 139 with his third visit.

Another 140 leaves double 11 - and Littler cannot take out 143.

But, no, Heta misses with three darts in hand - and Littler takes out 60 with double top and double 10! Unorthodox finish but he won't care!

A huge 180 from Heta followed by a 127 gives him a chance for a crucial break of throw.

And he nails double 18 first dart - he's throwing for the match.

The crowd senses a Littler fightback after he punishes a very poor leg from Damon Heta by taking out 68 via double top.

Image source, Kieran Cleeves/PDC

The 14th leg is an uncharacteristically scrappy one with both players struggling for trebles early doors.

Their averages have dipped after that crazy start but that was inevitable - and they are still both well in triple figures.

The 17-year-old halts that losing streak of five legs with a 11-dart effort, capped by a double top finish.

It's only a hold of throw, mind.

Now it's Luke Littler's turn to go close to a massive finish, missing the bull - by a fair margin to be honest - to take out 167.

And Heta takes full advantage by landing tops. That's five straight legs for the Aussie.

Image source, Kieran Cleeves/PDC

This could be the match.

Damon Heta is inches from taking out the big 170 finish but misses the bull.

However, Luke Littler chucks away three darts at double and is punished by the Australian who opens up a three-leg lead and is playing inspired stuff.

Damon Heta gave it the big one after winning those two legs before the break.

Very animated celebration - and rightly so.

But Luke Littler looked a tad irked by it - can he use that to respond in the second half of the match?

Alan Warriner-Little
Former World Grand Prix champion on ITV4

When you see games of this standard, breaks of throw don't come along that often. But Damon Heta has got that one break.

Treble 20, treble 11 and double 14.

Damon Heta makes it look as easy as you like - and the Aussie is absolutely on fire.

Luke Littler has another "off" leg - this time on his own throw.

Damon Heta just misses double 11 for a break - and Luke Littler is inches away from a 155 finish, just missing double 19 after a 60 and 57.

But Heta hits double 11 to punish him - and that's the first break of the match.

A rare poor leg from one player with Luke Littler all the way back on 285.

Damon Heta should finish it off but misses two darts at double four and two - decides to bust his score and go back to four next time, which he lands.

Image source, Kieran Cleeves/PDC

Alan Warriner-Little
Former World Grand Prix champion on ITV4

I've been in this game for over 30 years and I've never seen darts like this from both players.

I think they're both enjoying it as well, they're feeding off each other.

Luke Littler replies with a 10-dart leg, finishing on tops.

Both players are averaging over 120 - this is on course to be one of the greatest darts matches of all time.

Damon Heta comes back from the break with a - yeah you guessed it - 180. Then a 177 soon after.

That pushes his average up to 127.

He takes out 91 with treble 17 and tops. This is stunning, stunning darts.

Image source, Kieran Cleeves/PDC

When some folk say people are getting carried away by Luke Littler, well it's because of performances like this.

But Damon Heta is matching him stride for stride. This is going to be a belter - well it is already.

Damon Heta is averaging 125.64 - that's just out of this world, even if it is over a small sample of five legs.

Yet he's behind to Luke Littler, who is averaging 118.93 and has been deadly on the doubles - under intense pressure from his opponent.

180, 180, 140, 140.

That's all you keep hearing from the scorer.

And with Heta lurking on a finish, the teenager nails double 10 last dart in hand to end a frankly awesome opening mini-session.

Stuart Pyke
Commentator on ITV4

This, believe you me, is as good as it gets. They're both averaging 120 each and we're in leg five!