Roberts, also a key member of that team, now stands at 72 Test caps - and the 28-year-old believes Wales must make full use of their increased experience this time around.
"We go into the World Cup as a very experienced team," Roberts told ESPN.
"There is a lot of knowledge of the game and a lot of guys who have played at the top level for quite a while now and that's going to stand us in good stead in the big games.
"We've come a long way. Certainly the few months' preparations going into the World Cup have been very difficult but we've made sure we're in peak condition.
"In 2011 we surprised a lot of people and the pressure is on us now to repeat that."
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