Two tries from full-back Jordan Williams helped Dragons to a bonus-point win over Italian opponents Zebre at Rodney Parade.

Zebre responded with tries from centres Federico Mori and Giulio Bisegni.

Italy fly-half Carlo Canna also added eight points while Sam Davies missed four kicks at goal for the hosts.

Prop Leon Brown and full-back Williams returned after missing Dragons' opening round 35-5 defeat against Leinster in Dublin.

With Wales back-rower Aaron Wainwright unavailable through injury, Taine Basham was named at openside flanker and Harrison Keddie moved to blindside.

Zebre coach Michael Bradley made five changes from the side that lost to Cardiff Blues, including a return for number eight David Sisi.

Dragons opened the scoring through full-back Williams after a powerful initial burst from Wales centre Roberts on his home debut. Davies' conversion hit the post.

Roberts and Williams swapped roles for Dragons' second try. Full-back Williams made a superb incisive burst after a Nick Tompkins long pass before he was pulled down just short of the Zebre line, with the supporting Roberts diving over.

Canna opened Zebre's account with a penalty, before hooker Dee, left out of the Wales squad this week, was driven over for the hosts' third try.

Basham, also not included in Wayne Pivac's squad, proved his worth to Dragons with some trademark turnover penalties.

Zebre wing Mattia Bellini was yellow-carded just before half-time but Dragons somehow managed not to score following an inexplicable chip-kick from Dee.

To compound matters, the visitors took advantage with a runaway try from centre Mori to reduce the half-time deficit to 15-10.

So instead of finishing the first half with the bonus-point try, the home side only found themselves just five points ahead.

That advantage was reduced to two points with an early second-half Canna penalty.

Dragons ensured the bonus point thanks to excellent approach work from Roberts, with Williams benefitting with his second try.

Former Leicester prop Greg Bateman made his first Dragons appearance from the replacements bench.

Although fly-half Davies missed all four conversions, he slotted over two late penalties

Zebre crossed for their second try through captain Bisegni on his 100th appearance for the Italian club.

A missed Antonio Rizzi conversion meant Zebre were denied a losing bonus point.

Dragons director of rugby Dean Ryan said: "I am not very satisfied. It is a game where after 35 minutes of the first half we had a lot of control and then missed some clinical moments.

"We have to analyse what is going on in those moments because we had them against Leinster and had them again.

"Although we had control of the game, it forced us into a more cagey game in the second half when we should be surging away.

"It was a game easy for us to move through the gears and show what we can do. We keep dragging ourselves down and making it a tighter contest than it needs to be.

"Twelve months ago we would celebrate anything that happened. That has changed now and if this group wants to get better and keep pressure up internally, it needs to hold itself to account."

Dragons: Jordan Williams; Jonah Holmes, Nick Tompkins, Jamie Roberts, Ashton Hewitt; Sam Davies, Rhodri Williams (c); Brok Harris, Elliot Dee, Leon Brown, Joe Davies, Matthew Screech, Harrison Keddie, Taine Basham, Ross Moriarty.

Replacements: Richard Hibbard, Greg Bateman, Aaron Jarvis, Joe Maksymiw, Ben Fry, Tavis Knoyle, Josh Lewis, Adam Warren.

Zebre: Jacopo Trulla; Junior Laloifi, Giulio Bisegni (c), Federico Mori, Mattia Bellini; Carlo Canna, Guglielmo Palazzani; Daniele Rimpelli, Marco Manfredi, Eduardo Bello, Leonard Krumov, Ian Nagle, Maxime Mbandà, Johan Meyer, David Sisi.

Replacements: Massimo Ceciliani, Danilo Fischetti, Giosue Zilocchi, Cristian Stoian, Mick Kearney, Nicolò Casilio, Antonio Rizzi, Lorenzo Masselli.

Referee: Chris Busby (IRFU)

Assistant Referees: Adam Jones, Craig Evans (both WRU)

TMO: Sean Brickell (WRU)