Holders Wales got their bid for an historic hat-trick of Six Nations titles off to a nervy start when they squeezed past a dogged Italy 23-15 in the opening match on Saturday (local time).
First-half tries by Alex Cuthbert and Scott Williams gave the hosts a handy 17-3 lead at the break.
Michele Campagnaro, 20, gave Italy hope of snapping a 15-match away losing streak in the championship with two tries to make the deficit five points with 10 minutes remaining.
Leigh Halfpenny's third penalty then gave Wales some breathing space as they made sure there was no repeat of their opening-day defeat by Ireland in 2013.
Wales, looking to become the first team to win three consecutive Six Nations titles outright, will be satisfied with the victory but will want an improved effort in the scrum as they eye tougher challenges in the coming weeks.
France host England in Paris later today while Ireland and Scotland clash in Dublin tomorrow.
Wales 23 (Alex Cuthbert, Scott Williams tries; Leigh Halfpenny 2 conversions, 3 penalties) Italy 15 (Michele Campagnaro 2 tries; Tommaso Allan conversion, penalty). HT: 17-3