Scarlets produced a stirring second-half comeback, but came up just short, losing 29-28, in a thrilling Rainbow Cup clash against Cardiff Blues at Parc y Scarlets.

The home side trailed 26-9 midway through the second half, but two tries from replacement scrum-half Dane Blacker and another by Angus O’Brien put them within sight of a stunning victory.

However, a late penalty from man of the match Jarrod Evans stole the spoils for the visitors, who claimed a third victory over their West Wales rivals this season.

Scarlets were on the scoreboard early thanks to the boot of full-back Halfpenny, but they were then forced on the defensive for long periods as the visitors piled on the pressure.

With Evans pulling the strings, the fly-half crossed for the first try on six minutes and it needed a superb cover tackle from Tom Rogers to deny Josh Turnbull in the corner.

The Blues did get their third try when lock Cory Hill charged over on 23 minutes, but a second Halfpenny penalty kept the Scarlets in contention after skipper Ryan Elias had been held up over the line.

However, no sooner had the Scarlets got on the board than the Blues were celebrating their third try by full-back Hallam Amos. A third Halfpenny penalty on the stroke of half-time reduced the deficit to 19-9, but the Scarlets still had plenty of work to do.

That mountain got bigger when Turnbull crashed over for the Blues’ bonus-point try and it looked like the points were in the bag for the visitors.

But back came the Scarlets with an outstanding comeback sparked by Blacker.

The former Blues scrum-half followed up Johnny McNicholl’s weaving break to cross on 64 minutes, then popped up again on Tom Rogers’s shoulder for his second.

With Angus O’Brien and Dan Jones kicking intelligently, momentum continued to swing the Scarlets’ way and with six minutes remaining they snatched the lead thanks to a lovely dink through from Dan Jones, which O’Brien plucked out of the air to cross at the posts.

O’Brien’s conversion put the Scarlets ahead, but in a dramatic finale, the Blues were awarded a penalty and Evans held his nerve.

There was still time for a final twist. Referee Sean Gallacher awarded the Scarlets a penalty for a high tackle with two minutes remaining, but changed his mind and it was the Blues who saw out the game to claim the narrowest of victories.