Ulster booked their place in the RaboDirect PRO12 final with a 28-17 victory over Scarlets at Ravenhill on Friday night.

First half tries from Tommy Bowe and Robbie Diack along with another score early in the second half from Tom Court paved the way for Mark Anscombe's side to progress to the league's showdown while South African Ruan Pienaar kicked 13 points from three penalties and two conversions.

Ulster's cause was also bolstered by storming displays from Nick Williams and man of the match Rory Best while an eye-catching display from Ulster's sole Lions representative Bowe also helped the home side on their way.

The Scarlets, who were making their first appearance in the play-offs, produced another flat display in the wake of last week's home thumping by Treviso and their failure to score any points between the third and 60th minute told its own tale.

The Scarlets opened the scoring with a third minute penalty from Owen Williams - a late replacement for Rhys Priestland - but Ulster quickly equalised through Pienaar two minutes later. After that it was cagey stuff from both sides with the primary option being to largely just kick the ball at each other.

This situation pretty much continued until Williams had a shot at goal after 17 minutes but the ball hit the right upright and Ulster cleared. That seemed to up the ante and shortly after a tremendous break from Jared Payne, a melee in the Scarlets 22 saw referee Alain Rolland send Andrew Trimble and Liam Williams to the bin though Payne had just managed to touch down from a Pienaar cross-kick.

Ulster then began to turn the screw with Nick Williams - winner of two end of season awards earlier this week - in the thick of it and after the Kiwi had driven on from a lineout near the Scarlets line, Pienaar switched the attack to the blindside and Bowe stepped inside fellow Lions squad member George North to score.

Pienaar added a marvellous conversion and Ulster looked well on top at 10-3 though that lead should have been increased but Pienaar was wide with a 29th minute penalty attempt as both sides returned to full complements.

Five minutes later, though, Ulster scored again with Diack touching down at the back of a rumbling maul off a lineout close to Scarlets' line in the same corner as Bowe's earlier effort. Pienaar's conversion hit an upright keeping Ulster's lead at 15-3.

But after Williams helped force a turnover and a huge scrum from Ulster the half ended with Pienaar slotting a straightforward penalty and the home side trooped off leading 18-3.

Three minutes after the restart, Court drove over from close range after Darren Cave's inside burst, both of which followed a mix-up in the Scarlets defence allowing Trimble and Rory Best to take the ball into the visitors' 22. The TMO was brought in on the decision, despite the referee initially awarding the score, and Pienaar converted to take it to 25-3.

The game then appeared to settle down into a fairly uneventful period which was only altered by substitute Gareth Davies dancing through on the hour mark to score the visitors' first points since the third minute with Williams converting.

Pienaar then nailed a 62nd minute penalty to push Ulster up to 28-10 and most of the remainder was about both sides emptying their benches and Ulster players avoiding injury ahead of their final appearance at the RDS the week after next.

The Scarlets, though, did finish the stronger and substitute Sione Timani got over in the 78th minute for a consolation score with Williams again adding the extras.