Rugby World Cup 2015: Wales' Jamie Roberts 'motivated' by 2011
|Rugby World Cup warm-up: Ireland v Wales|
|Venue: Aviva Stadium, Dublin Kick-off: 14:30 BST, 29 August|
|Coverage: Live on BBC Radio Wales and Radio Cymru; Scrum V highlights on BBC Two Wales and iPlayer|
Centre Jamie Roberts says he is still haunted by Wales' World Cup semi-final defeat in 2011.
Wales begin their World Cup campaign against Uruguay on 20 September before playing England, Fiji and Australia.
Warren Gatland's side lost 9-8 to France four years ago, with captain Sam Warburton sent off after 17 minutes.
"I'd love to be able to rectify that with this team and go a step further," Roberts said.
Wales finished fourth at the 2011 World Cup after losing to Australia in the bronze medal match.
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But Roberts, 28, still feels the pain of losing to Six Nations rivals France in the last four in New Zealand.
"Four years ago was an amazing experience for everyone involved," Roberts added.
"For me I think it was one of the biggest missed opportunities in Welsh rugby history.
"To lose a semi-final by a point in a game we should have won, regardless of the red card, was bitterly disappointing.
"It's a game that will haunt me for the rest of my career and probably the rest of my life. For me it's a motivating factor."
Nine of the team that started against France in Auckland in 2011 are in the Wales training squad preparing for this year's World Cup.
The final squad of 31 players will be announced on Monday, 31 August - two days after Wales play Ireland in Dublin in a warm-up match.
British and Irish Lions trio Mike Phillips, James Hook and Richard Hibbard were among eight players dropped from the squad earlier in August.
Harlequins-bound Roberts starts against Ireland but says no player is taking their place in the final squad for granted with seven set to miss out.
"They guys are well aware that 38 doesn't go into 31 and everyone needs to put good performances this weekend," Roberts said.
"You can't go off and do your own thing. It's about the team and it's about the team winning.
"I'm sure the coaches are aware of that and they'll pick the 31 guys who they think that can win the World Cup with Wales."