Leinster centre Fergus McFadden returned to club form with a bang to kick a last-minute penalty and secure his side's 12th successive Pro 12 victory with a nervy 16-13 triumph over the Scarlets.

McFadden, dropped by Ireland after their opening Six Nations match against Wales, scored all of Leinster's points in a virtuoso display to remind Declan Kidney of his ability and maintain the Irish province's lead at the top of the table.

For a while it looked as if the play-off chasing Scarlets were about to upset the formbook and come away from the RDS Arena with a memorable victory but they could not hold on.

Meanwhile, Cardiff flyhalf Dan Parks may have hung up his international boots this month but the former Scotland international produced an inspired performance as Cardiff battled back from a half-time deficit to beat Ulster 21-14.

Cardiff made it five wins from their last six games but in difficult conditions it was the performance of Parks, who scored 16 points including a second half try that saw off a spirited Ulster showing.

No.8 Robbie Diack was the star of the first-half as Ulster looked set to continue their recent impressive form and avoid a Pro 12 clean sweep in Wales this season.

In Friday's final match Dan Biggar's boot got Steve Tandy's reign off to a flying start as the Welsh region kept up the pressure on table-topping Leinster with a comfortable 23-7 victory over Aironi.

Following the resignation of director of rugby Scott Johnson and head coach Sean Holley in midweek Tandy resided over his first game in the Pro 12 and must have been pleased with what he saw from the Welsh flyhalf.

With 16 players absent on international duty with Wales, Ireland and various Under-20 squads, the former Bridgend Ravens head coach had little choice with his team selection but welcomed back captain Alun Wyn Jones from a toe injury for his first match since November.

All the scores and scorers from the Friday games:

Leinster 16-13 Scarlets

Scorers:

For Leinster:
Try: McFadden
Con: McFadden
Pens: McFadden 3

For Scarlets:
Try: Newton
Con: S. Jones
Pens: S. Jones, Newton

Leinster: 15 Isa Nacewa, 14 David Kearney, 13 Eoin O'Malley, 12 Fergus McFadden, 11 Fionn Carr, 10 Ian Madigan, 9 Eoin Reddan, 8 Rhys Ruddock, 7 Shane Jennings, 6 Kevin McLaughlin (captain), 5 Devin Toner, 4 Damian Browne, 3 Jamie Hagan, 2 Sean Cronin, 1 Jack McGrath.
Replacements: 16 Richardt Strauss, 17 Heinke van der Merwe, 18 Nathan White, 19 Leo Auva'a, 20 Dominic Ryan, 21 Isaac Boss, 22 Noel Reid, 23 Brendan Macken.

Scarlets: 15 Dan Newton, 14 Liam Williams, 13 Gareth Maule (captain), 12 Scott Williams, 11 Andy Fenby, 10 Stephen Jones, 1 Rhodri Jones, 2 Emyr Phillips, 3 Deacon Manu, 4 Sione Timani, 5 Dominic Day, 6 Josh Turnbull, 7 Johnathan Edwards, 8 Kieran Murphy
Replacements: 16 Craig Hawkins, 17 Phil John, 18 Peter Edwards, 19 Damian Welch, 20 Ben Morgan, 21 Liam Davies, 22 Adam Warren, 23 Viliame Iongi.

Blues 21-14 Ulster

The scorers

For Cardiff Blues:
Tries: Parks, James
Cons: Parks 3
Pen: Parks

For Ulster:
Try: Diack
Pens: Pienaar 3

Yellow card: Ian Humphreys

Cardiff Blues: 15 Ben Blair, 14 Richard Mustoe, 13 Gavin Evans, 12 Gavin Henson, 11 Tom James, 10 Dan Parks, 9 Lloyd Williams, 8 Xavier Rush, 7 Martyn Williams, 6 Michael Paterson, 5 Paul Tito (captain), 4 Cory Hill, 3 Scott Andrews, 2 Ryan Tyrell, 1 John Yapp.
Replacements: 16 T Rhys Thomas, 17 Nathan Trevett, 18 Ryan Harford, 19 Maama Molitika, 20 Macauley Cook, 21 Richie Rees, 22 Ceri Sweeney, 23 Chris Czekaj.

Ulster: 15 Stefan Terblanche, 14 Craig Gilroy, 13 Nevin Spence, 12 Paddy Wallace, 11 Ian Whitten, 10 Ian Humphreys, 9 Ruan Pienaar, 8 Robbie Diack, 7 Willie Faloon, 6 Chris Henry (captain), 5 Dan Tuohy, 4 Lewis Stevenson, 3 John Afoa, 2 Nigel Brady, 1 Tom Court.
Replacements: 16 Andi Kyriacou, 17 Paddy McAllister, 18 Adam Macklin, 19 Tim Barker, 20 Mike McComish, 21 Paul Marshall, 22 Simon Danielli, 23 Adam D'Arcy.

Ospreys 23-7 Aironi

Scorers

For Ospreys:
Tries: Penalty try, Bishop
Cons: Biggar, Morgan
Pens: Biggar 3

For Aironi:
Try: Sinoti
Con: Olivier

Yellow card: Mauro Bergamasco

Ospreys: 15 Richard Fussell, 14 Hanno Dirksen, 13 Andrew Bishop, 12 Ashley Beck, 11 Eli Walker, 10 Dan Biggar, 9 Rhys Webb, 8 Joe Bearman, 7 Sam Lewis, 6 Tom Smith, 5 James King, 4 Alun Wyn Jones (captain), 3 Joe Rees, 2 Richard Hibbard, 1 Ryan Bevington.
Replacements: 16 Scott Baldwin, 17 Duncan Jones, 18 Will Taylor, 19 James Goode, 20 George Stowers, 21 Kahn Fotuali'i, 22 Matthew Morgan, 23 Tom Isaacs.

Aironi: 15 Alberto Benettin, 14 Giulio Toniolatti, 13 Gilberto Pavan, 12 Gabriel Pizarro, 11 Sinoti Sinoti, 10 Naas Olivier, 9 Tito Tebaldi, 8 Simone Favaro, 7 Mauro Bergamasco, 6 Nicola Cattina, 5 Carlo Del Fava, 4 Joshua Furno, 3 Lorenzo Romano, 2 Roberto Santamaria (captain), 1 Matias Aguero.
Replacements: 16 Antonio Denti, 17 Alberto De Marchi, 18 Salvatore Perugini, 19 George Biagi, 20 Luca Redolfini, 21 Tyson Keats, 22 Riccardo Pavan, 23 Matteo Pratichetti.