Wales maintained hope of retaining their Six Nations title with a clinical victory over Italy in rain-lashed Rome.
Three Leigh Halfpenny penalties, to two from Kris Burton, gave the visitors a 9-6 interval lead.
Converted tries from Jonathan Davies and Alex Cuthbert and a further Halfpenny kick put Wales in command at 26-9 on the hour.
They kept the hosts at bay with some comfort in a scrappy final quarter to record a sixth consecutive win over the Azzurri.
It was also a fourth successive away victory for Wales in the Championship - a feat they last achieved in 1979.
A fifth - against Scotland at Murrayfield in a fortnight - would see them welcome England to Cardiff on the final day with a possible title still in their sights.
But for now they can reflect on a satisfying afternoon in Rome where their scrummaging prowess and efficient finishing from limited opportunities paved the way for victory.
With rain falling incessantly all morning, any hopes of an attractive spectacle had disappeared before kick-off.
A slow-paced game full of scrums and territorial kicking should have suited the hosts, but it was Wales who prospered in the set-piece battle.
The visitors' dominant scrum earned three successive penalties in the 13th, 15th and 18th minutes as veteran Italian prop Andrea Lo Cicero, equalling Alessandro Troncon's Italian record of 101 caps, endured a torrid time.
Halfpenny punished the second and third offences by kicking Wales into a 9-3 lead after 20 minutes.
His opening penalty, after Italy had fallen offside in midfield trying to repel a Wales attack, was swiftly cancelled out by Burton in the 10th minute before Wales took command.
But their dominance failed to yield further reward as Italy - without talismanic number eight Sergio Parisse - ended the first half only three points adrift.
Burton, under pressure from Dan Biggar, was off target with a drop-goal attempt after Cuthbert had spilled a catch forward to give Italy a scrum five metres out.
But with the rain hammering down, the hosts' scrum recovered sufficiently to win a penalty, allowing Burton to reducing the deficit to 6-9.
Attacking rugby and try-scoring opportunities were at a premium in the treacherous conditions. Italy's one chance came after Halfpenny had a clearing kick charged down, but the full-back recovered to make a crucial tackle on Giovanbattista Venditti as the Azzurri wing threatened.
Wales might have fashioned a score after 31 minutes when Biggar caught a high kick on the right touchline and released Cuthbert. The giant wing appeared to be clear of the cover, only for a superb tap tackle from Gonzalo Canale to snag him.
Wales maintained the pressure as Italy struggled to get out of their own 22 and won another penalty, only for Halfpenny's radar to fail him for the first time.
The opening exchanges of the second half effectively decided the contest, with Wales enjoying a touch of fortune at two pivotal moments.
First, as Italy rampaged their way to within metres of the Welsh line, Biggar appeared to tackle Tommaso Benvenuti without the ball as the centre tried to scoop it up and touch down.
It was a marginal call that went in Wales' favour, and they were also slightly fortunate with their opening try after 44 minutes.
Mike Phillips, picking up at the base of a ruck, launched a chip over the defence, and the bounce flummoxed both Burton and Edoardo Gori as a grateful Davies - who had barely touched the ball until that moment - gobbled it up to score.
Halfpenny's conversion gave Wales a 10-point cushion, but Paul James - on as a replacement for the injured Gethin Jenkins - infringed to allow Burton to cut the deficit to 9-16.
But the 10-point margin was quickly restored as Wales won a fourth penalty at the scrum, and Halfpenny stroked over a superb kick from the left touchline.
Wales' cause was boosted further when referee Romain Poite lost patience with the Italian scrum and dispatched captain Martin Castrogiovanni to the sin-bin just before the hour.
The visitors took immediate advantage, Cuthbert hitting a superb line onto Biggar's pass - with Canale fooled by Davies's dummy run - to sprint over in the left corner for his seventh Test try.
Halfpenny's conversion made it 26-9, allowing Wales to relax somewhat as the strains of "Hymns and Arias" briefly floated around the Stadio Olimpico.
With one eye on the final table, and the possibility of a title won on points difference, the visitors emptied their bench in search of further scores, but the match merely petered out.
Italy: Masi, Venditti, Benvenuti, G. Canale, McLean, Burton, Gori, Lo Cicero, Ghiraldini, Castrogiovanni, Pavanello, Minto, Zanni, Favaro, Vosawai.
Replacements: Garcia for G. Canale (63), Botes for Gori (65), De Marchi for Lo Cicero (54), Giazzon for Ghiraldini (54), Cittadini for Castrogiovanni (70), Geldenhuys for Minto (54), Derbyshire for Favaro (69).
Not Used: Orquera.
Sin Bin: Castrogiovanni (58).
Wales: Halfpenny, Cuthbert, Davies, Roberts, North, Biggar, Phillips, Jenkins, Hibbard, A Jones, Coombs, Evans, R. Jones, Tipuric, Faletau.
Replacements: S Williams for Roberts (71), Hook for Biggar (68), L. Williams for Phillips (63), James for Jenkins (45), Owens for Hibbard (51), Mitchell for A Jones (73), A Jones for Coombs (51), Warburton for R. Jones (68).
Ref: Romain Poite (France).