The New Zealand Warriors have kept their perfect 2008 NRL home record intact, overcoming the Canterbury Bulldogs 36-16.
The Warriors raced out to a 10-0 lead in as many minutes when wingers Patrick Ah Van and Manu Vatuvei both crossed the line.
That save proved the turning point for the Bulldogs in the first half and they hit back with two tries to lead 12-10 at halftime.
Firstly a Sonny Bill Williams-inspired break led to a Luke Patten four-pointer, then Roberts waltzed through a leak in the home side's defence.
It was all the Bulldogs in the early running of the second half but the Warriors were more decisive when presented with try-scoring opportunities.
Vatuvei notched his third double of the year, Sonny Fai scored his first in Warriors colours and Lance Hohaia and Ruben Wiki also got across the line.
A try to Heka Nanai was all the Bulldogs had to show for their second-half efforts as they failed to bounce back from last week's 12-40 hiding by the Roosters.