The hotly anticipated clash between the pre-tournament favourites Ireland and form team Wales never looked close, as Anscombe punished a stream of Irish infringements with his goal kicking in the swirling rain.
Welsh centre Hadleigh Parkes scored his side's only try after barely 80 seconds had been played, collecting a deft Anscombe chip, while Ireland's Jordan Larmour left it until the final minute to bag an opening score that would have been scant consolation.
The Welsh win leaves England unable to catch up even if they beat Scotland later on Saturday, and will stoke hopes of a serious Wales tilt at this year's Rugby World Cup, which kicks off in Japan in September.
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