A red card for prop Michele Rizzo meant Edinburgh's fightback was all too brief as the defending champions Scarlets romped to a bonus-point 28-8 win.

The Italian tried to clear out a ruck on the Edinburgh line, but he charged into the head of Scarlets scrum-half Gareth Davies.

He was always in trouble and it was the sort of incident which looked worse in the TV replays. Given the current policies of protecting the head, Irish referee John Lacey really had little choice but to reach for his red card.

Rizzo is on loan to Edinburgh as cover for their injured loosehead props. It looks like he may be spending some or maybe even all of the rest of the loan period suspended as a result.

Edinburgh had fought their way back into the game with captain Magnus Bradbury leading the way in attack and defence, but that dismissal put paid to any hopes of an unlikely win.

In many ways, this game was a crucial early test for the Richard Cockerill era in charge at Edinburgh. Could he get a reaction following on from a poor defeat at home to the Italians of Treviso?

Seven changes smacked of a determination to get the message through that performances like that would have consequences, but an way trip to the champions would hardly be the fixture of choice when looking for a bounce back.

Plenty of changes, including wing Damien Hoyland going from playing his 50th game for Edinburgh to an afternoon of club rugby. He was replaced by local Scarlets lad Jason Harries, from Carmarthen and Wales Sevens but now plying his professional trade for Edinburgh.

Many of the alterations hardly weakened the team, for example Stuart McInally and WP Nel came into the front row. In fact, it may even have been a return to a stronger line-up after trying some experiments for Benetton Rugby at home.

The competition needs a strong Edinburgh challenge as there is already a danger of Ulster, Leinster and Scarlets running away with the top three play-off spots. A three-horse race in Conference B is not in anyone's interest.

The Scarlets showed right from the start why they are hot favourites to challenge hard for the title again, maintaining the ball-in-hand approach which served them so well last season.

However, Edinburgh were clearly determined to play with pace themselves and had also done their homework on the way the Scarlets use the blindside wing in open play.

The Scarlets, though, are nothing if not persistent in the way they play, working on the basis that if they keep probing then the gaps will appear from somewhere.

In the end, they did work space down the right hand side and won a penalty when Edinburgh full-back

went to ground offside in the ruck in his desperation to kill the move. Scrum-half Gareth Davies took a quick tap which caught out Edinburgh.

Although he was tackled just short of the line, outside-half Rhys Patchell was able to go over for the try from the ruck ball won quickly and it was converted by Leigh Halfpenny.

Then Scotland captain Johnny Barclay, playing for the Scarlets of course, went off injured though that did give the home crowd the chance to show their appreciation for his efforts.

It did not stop the wave after wave of Scarlets attacks and if Gareth Davies had made the first try, he was able to get his own name on the scoresheet for the second running in from 10 yards after more quick ball in the Edinburgh 22 and handing Halfpenny another conversion success.

Edinburgh did get themselves back into the game before half-time, firstly through a Duncan Weir penalty from in front of the posts 35 yards out.

Then, just before the break, Harries got his reward with a run at an angle from the middle of the field out towards his left wing, after the ball came back from a break up the left by hooker Stuart McInally and flanker Hamish Watson.

It was a well taken try to put his team back within a score. Weir missed the touchline conversion but still the half-time team talk would have been a little more positive.

However, the air would soon have turned blue in the Edinburgh camp as they were down to 14 men and any chance was also realistically gone.

Rizzo saw red and to rub salt in the wound the Scarlets scored their third try from that penalty, with replacement prop Werner Kruger going over.

They soon earned the bonus point fourth try, excellent team handing putting flanker Aaron Shingler clear on the left for him to score from the overlap. Halfpenny maintained his perfect kicking record with a fourth conversion.

The 14 men of Edinburgh battled all the way to the end and even kept attacking, but were never likely to breach the Scarlets defence.

They can however take consolation from the fact they held out themselves and managed to limit the damage.