South Wales Police says missing Ben Thompson from Haverfordwest had been enjoying the rugby international in Cardiff on Saturday.
The 34-year-old was last seen in Cardiff city centre on Saturday.
He is described as 5' 9" tall, with short brown hair and blue eyes, and he was last seen wearing brown boots, blue jeans, and possibly a blue & a white striped top with a green jacket.
Anyone with information is asked to call their local police on 101.
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It will be wet and windy this evening and through much of tonight with some heavy rain at times.
Welsh golfing legend Ian Woosnam has set his sights on securing a home victory at the Wales Senior Open in Newport.
It will be a bright start to Saturday, with some sunny spells. However, cloud and rain will reach the far west by late-afternoon.