Rome - Second-half tries by Jonathan Davis and Alex Cuthbert helped seal a 26-9 win over Italy and keep Wales' Six Nations title defence on track in difficult conditions at the Stadio Olimpico here on Saturday.Wales went in at half-time 9-6 to the good after Leigh Halfpenny kicked three penalties to the two converted for the hosts by Kris Burton.However, neither team would boast of dominating the other in a dire opening half beset by periodic spells of heavy rain.Wales, looking for their second win of the tournament having beaten France in Paris after an opening defeat to Ireland, finally found their stride after the interval."It was a good performance, especially up front," said Davies. "The boys were fantastic and worked really hard. As a backline we had to keep our errors down and put them in the right places."To be fair, the pack were on fire today."Italy, however, were unlucky not to be rewarded in the first minute of the second half when the Welsh defence were guilty of handling errors. Only Tomasso Benvenuti's failure to collect the ball and carry it over the tryline from two metres out stopped the hosts from earning a potential game-changing try.In near desperation minutes later Burton tried to make amends but, for the second time in the game, missed a drop goal from 30 metres out.Italy were without captain Sergio Parisse, who was banned for 30 days after insulting the referee while playing for Stade Francais.Although his replacement, Fijian-born No 8 Manoa Vosawai, proved efficient, Parisse's absence appeared to tell as the hosts failed to really get going as they had against France in a 23-18 win in their tournament opener.Italy's earlier fumble was to prove costly minutes later when they failed to deal with Mike Phillips' short kick deep into territory, allowing Davies to collect from five metres out and touch down unchallenged.Halfpenny converted to give Wales a 16-6 lead.To their credit, Italy - who succumbed 34-10 to Scotland in their second game at Murrayfield - responded positively.After fullback Andrea Masi's kick into touch deep in Welsh territory, the hosts won the line-out and briefly threatened metres out from the tryline.Minutes later Burton gave Italy their first points of the half when he kicked a penalty from 25 metres out, however the arrival of Paul James and Alun Wyn Jones to the Welsh pack immediately paid dividends when yet another Italian scrum infringement gave the visitors a penalty.From 40 metres out, Halfpenny saw his angled kick go between the posts to restore Wales' 10-point lead.Italy replaced Andrea Lo Cicero, Ghiraldini and Francesco Minto with Davide Giazzon, Alberto De Marchi and Quintin Geldenhuys respectively in the 55th minute.But despite a brief flurry inside Wales' 22, Italy were left a man down when Martin Castrogiovanni, standing in as captain for Parisse, was sin-binned for persistent infringements at the scrum.A superb push to the Italian 22 by Phillips gave Wales possession and when Gonzalo Canale was caught cold by a dummy runner, Cuthbert was free to run through for his seventh try in 16 international matches.Halfpenny's flawless kicking continued when he converted from the right touchline to give the visitors a virtually unassailable lead of 26-9.Italy then failed to capitalise at the lineout after Burton kicked a penalty deep into territory.Wales sent on Sam Warburton, who captained the side to the semi-finals of the 2011 World Cup but started on the bench, although he replaced Ryan Jones and not Justin Tipuric.James Hook also provided some extra spark for the remainder, in which a toothless Italy failed to threaten.