James Hook
Former Wales fly-half on BBC Radio Wales

That's a pretty early change for Cardiff with Iwan Stephens coming off.

Looks like a tactical change as Harri Millard comes on. Stephens is the son of former Llanelli 10 Colin.

It's Cardiff who make the first change

Iwan Stephens makes way for Harri Millard on the wing.

James Hook
Former Wales fly-half on BBC Radio Wales

Cardiff made a nuisance of the breakdown in the first half and are doing it again.

There was a really good tackle there from Callum Sheedy on Ioan Lloyd, had to make it down on the Scarlets bootstraps.

Matt Lloyd
BBC Sport at Parc Y Scarlets

When you look at the two replacements benches, I'd say Cardiff have more firepower in Mackenzie Martin and Ellis Bevan as well as some real know-how in Ed Byrne and Tinus de Beer.

Come the hour-mark, that could prove the difference.

It's a messy restart and Cardiff are being spoken to here about their rising penalty count.

James Hook
Former Wales fly-half on BBC Radio Wales

I think Ben Thomas has been good at 12, some would argue his best position.

I thought Ioan Lloyd went well stepping in for Sam Costelow last week and Gareth Anscombe last night for Gloucester too. Could he push his way into the Wales 10 jersey?

We are back under way at Parc y Scarlets.

A bit of a shock as Munster have gone down 42-33 to Zebre in Parma.

Bulls have beaten Edinburgh 22-16, and Lions were 35-22 winners over Ulster.

Today's attendance is 7,394 and that's in the absence of many travelling fans... judging by the sounds from the stands.

After today's derby, the action moves across the River Lougher as Ospreys take on Stormers in the United Rugby Championship.

It's set to be a special night for scrum-half Reuben Morgan-Williams who will make his 100th appearance for the Welsh region.

Ospreys have named an unchanged starting XV after narrowly losing their opening game 23-21 against Dragons.

You can read the team news here.

Matt Lloyd
BBC Sport at Parc Y Scarlets

That was a frantic first half and you wondered where it would end when Scarlets raced into a 15-0 lead inside 11 minutes.

But that brought the best out of Cardiff who have edged the breakdown battle, dominated the aerial battle and have hit back with two tries of their own.

Entertaining if harum scarum stuff and nicely set up for the second half.

James Hook
Former Wales fly-half on BBC Radio Wales

It was an entertaining first 10 or 12 minutes, I know I missed the first five!

Great start from the Scarlets,15 points up, it was plain sailing for them.

Cardiff turned down some kickable penalties and it paid off for them with Liam Belcher's try and then Mason Grady as well.

They will be the happier of the two sides with the scoreline come half-time.

The half is ending as it started with end-to-end action.

But the referee blows his whistle and Scarlets run down their tunnel with a three-point cushion.

James Hook
Former Wales fly-half on BBC Radio Wales

There's been some really good defence from Cardiff, another huge hit from Liam Belcher.

Scarlets front five had some good carries. You just feel that Scarlets have had four or five opportunities to score without adding to that early onslaught with those two tries in 10 minutes.

James Hook
Former Wales fly-half on BBC Radio Wales

There's been three big turnovers from Cardiff in the last few minutes.

The Ben Thomas strip, a rip by Josh McNally and now a bit of an unnecessary kick from Gareth Davies have allowed Cardiff to alleviate some pressure.

Matt Lloyd
BBC Sport at Parc Y Scarlets

There are four Wales fly-halves out there today... but the best boot belongs to Aled Davies.

The Cardiff scrum-half's box kicking has been absolutely on-point.

Whisper it quietly... but I bet Warren Gatland would be a fan of that!

It's getting a bit scrappy now as the half draws to a close.

Both sides are coughing up possession a little too easy.

James Hook
Former Wales fly-half on BBC Radio Wales

That was a let-off for Cardiff. Ben Thomas was really brave and put a big hit on Johnny Williams which caused the knock-on and Cardiff clear their lines.

Scarlets have made a mess of that.

Johnny Williams takes the ball up, falls awkwardly and Callum Sheedy wins the turnover.

It's a let-off.

James Hook
Former Wales fly-half on BBC Radio Wales

This is a huge chance for Scarlets, just five metres out with all their backs stacked to the right.