Celtic League leaders Leinster fought back from 19-7 down at half-time to beat the Scarlets at Lansdowne Road.
Leinster (7) 30
Tries: Jowitt, B. Blaney, Easterby, Dempsey
Cons: Contepomi 2
Pens: Contepomi 2
Scarlets (19) 22
Tries: I. Thomas, Byrne, G. Thomas
Cons: C. Thomas 2
Pens: C. Thomas
Cameron Jowitt replied with a Leinster try after Iestyn Thomas' score but Lee Byrne and Gavin Thomas added further Scarlets tries before the break.
Leinster punished Alix Popham's second half sin-binning with tries from Brian Blaney and Guy Easterby.
Ceiron Thomas' penalty levelled matters but a Contepomi penalty and Girvan Dempsey's try ensured the home win.
The Scarlets produced all the early pressure and fully deserved their seventh minute try from Iestyn Thomas with Ceiron Thomas adding the conversion.
Gordon D'Arcy's delightful sidestep set up Jowitt's try in the 13th minute and Contepomi's extras brought the sides level.
However, the Scarlets dominated the remainder of the first half with line-out problems afflicting the Leinster performance.
Lee Byrne notched the visitors' second try in the 19th minute after a flowing move and nine minutes later, Gavin Thomas crossed the Leinster line to extend the Scarlets' advantage to 19-7.
Contepomi's 46th minute penalty cut the Scarlets' lead and a minute later came the crucial moment of the match when Popham was sin-binned for one infringement too many.
With the man advantage, the Leinster pack rumbled over the Scarlets line in the 51st minute with Blaney getting the touchdown and more home pressure enabled scum-half Guy Easterby to snipe over for another try six minutes later.
After Ceiron Thomas' penalty had levelled matters again, the Scarlets wasted a glorious chance to notch a try in the 69th minute when Regan King's wild pass failed to find the totally unmarked Popham deep in the Leinster 22.
And Contepomi's 75th minute penalty and Dempsey's late try left the Scarlets without even the consolation of a bonus point as Leinster extended their Celtic League advantage to seven points.
Leinster: Girvan Dempsey, Rob Kearney, Braina O'Driscoll (capt), Gordon D'Arcy, Denis Hickie, Felipe Contepomi, Guy Easterby, Reggie Corrigan, Brian Blaney, Will Green, Bryce Williams, Malcolm O'Kelly, Cameron Jowitt, Keith Gleeson, Jamie Heaslip.
Replacements: Emmett Byrne, David Blaney, Niall Ronan, Eric Miller, Brian O'Riordan, John Hepworth, Kieran Lewis.
Scarlets: Lee Byrne; Dafydd James (capt), Matthew Watkins, Regan King, Mark Jones; Ceiron Thomas, Clive Stuart-Smith, Iestyn Thomas, Matthew Rees, Craig Dunlea, Vernon Cooper, Chris Wyatt, Dafydd Jones, Gavin Thomas, Alix Popham.
Replacements: Martyn Madden, Aled Gravelle, Francois Lowe, Gavin Quinnell, Liam Davies, Gareth Bowen, Barry Davies.