Two consecutive penalty misses from Priestland and Sexton followed before Rory Best scored Ireland's opening try in the 37th minute. Sexton added the extras giving the home side a 10-5 lead at the break.
Sexton opened up the scoring in the second half with a penalty after two minutes. Leigh Halfpenny, who took over the kicking duties from Priestland then added to the Welsh total with a penalty kick seven minutes later.
A converted Jonathan Davies try after fifty four minutes gave the visitors a two point lead however this didn't last long as Sexton kicked for goal five minutes later putting Ireland in front 16-15 with twenty minutes to go.
Ireland winger Tommy Bowe got over the line for the home side's second try which Sexton failed to convert giving Ireland a 21-15 lead in the 67th minute.
With just five minutes left on the clock Wales winger George North scored in the corner, Halfpenny failed to convert leaving Ireland ahead by one point.
Irish hopes of a grand slam were shattered when Stephen Ferris was penalised for a spear tackle in the final minute which the composed Halfpenny slotted to bring the final score to 21-23 in favour of the Welsh.
IRELAND: Rob Kearney (UCD/Leinster); Tommy Bowe (Ospreys), Fergus McFadden (Old Belvedere/Leinster), Gordon D'Arcy (Lansdowne/Leinster), Andrew Trimble (Ballymena/Ulster); Jonathan Sexton (St. Mary's College/Leinster), Conor Murray (Garryowen/Munster); Cian Healy (Clontarf/Leinster), Rory Best (Banbridge/Ulster), Mike Ross (Clontarf/Leinster), Donncha O'Callaghan (Cork Constitution/Munster), Paul O'Connell (Young Munster/Munster) (capt), Stephen Ferris (Dungannon/Ulster), Sean O'Brien (Clontarf/Leinster), Jamie Heaslip (Naas/Leinster).
Replacements: Sean Cronin (St. Mary's College/Leinster), Tom Court (Malone/Ulster), Donnacha Ryan (Shannon/Munster), Peter O'Mahony (Cork Constitution/Munster), Eoin Reddan (Lansdowne/Leinster), Ronan O'Gara (Cork Constitution/Munster), David Kearney (Lansdowne/Leinster).
WALES: Leigh Halfpenny (Cardiff Blues); Alex Cuthbert (Cardiff Blues), Jonathan Davies (Scarlets), Jamie Roberts (Cardiff Blues), George North (Scarlets); Rhys Priestland (Scarlets), Mike Phillips (Bayonne); Rhys Gill (Saracens), Huw Bennett (Ospreys), Adam Jones (Ospreys), Bradley Davies (Cardiff Blues), Ian Evans (Ospreys), Ryan Jones (Ospreys), Sam Warburton (Cardiff Blues) (capt), Toby Faletau (Newport Gwent Dragons).
Replacements: Ken Owens (Scarlets), Paul James (Ospreys), Andy Powell (Sale Sharks), Justin Tipuric (Ospreys), Lloyd Williams (Cardiff Blues), James Hook (Perpignan), Scott Williams (Scarlets).
Referee: Wayne Barnes (England)