Cardiff - 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.
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 on Saturday while Ireland and Scotland clash in Dublin on Sunday.
Wales – Tries: Alex Cuthbert, Scott Williams. Conversions: Leigh Halfpenny (2). Penalties: Halfpenny (3).
Italy – Tries: Michele Campagnaro (2). Conversion: Tommy Allan. Penalty: Allan.
Leigh Halfpenny; Alex Cuthbert, Scott Williams, Jamie
Roberts, George North; Rhys Priestland, Mike Phillips; Taulupe Faletau,
Justin Tipuric, Dan Lydiate; Alun Wyn Jones (capt), Luke Charteris; Adam
Jones, Richard Hibbard, Paul James
Replacements: Ken Owens, Ryan Bevington, Rhodri Jones, Andrew Coombs, Sam Warburton, Rhys Webb, James Hook, Liam Williams
McLean; Angelo Esposito, Michele Campagnaro, Alberto Sgarbi, Leonardo
Sarto; Tommaso Allan, Edoardo Gori; Sergio Parisse (capt), Mauro
Bergamasco, Alessandro Zanni; Marco Bortolami, Quintin Geldenhuys;
Martin Castrogiovanni, Leonardo Ghiraldini, Michele Rizzo
Davide Giazzon, Alberto De Marchi, Lorenzo Cittadini, Joshua Furno,
Francesco Minto, Tobias Botes, Luciano Orquera, Tommaso Iannone