Wales coach Warren Gatland praised his teams resolve in their 17-10 win over Samoa.
The victory locks in a quarter final berth provided the Welsh can win their remaining pool games against Fiji and Namibia.
An Anthony Perenise try helped Samoa to a 10-6 lead at the break before first five Rhys Preistland struck two penalties and Shane Williams finished off a long range try to secure the win.
Warren Gatland says he was proud of his teams second half effort.
"I thought we showed some great character today, behind at halftime boys dug deep in that second half. To do well in this World Cup you need a little bit of luck and you need to show some character and I think we did that today. I question perhaps a few years ago or 12 months ago, we might not have won that game."