Samoa sink Wales to boost Ireland
The Six Nations and Grand Slam champions have now lost five games in a row and were on the back foot straight away as Fa'atoina Autagavaia scored a try after just over a minute following a flowing drive marked by missed Wales tackles.
The hosts went in 13-10 ahead at the break, albeit against the run of play thanks to Ashley Beck's breakaway try.
With Mike Phillips recalled as scrum-half, Wales started with usual captain Sam Warburton on the bench but eight changes from the defeat by Argentina last weekend failed to spark the home side under interim coach Rob Howley.
The Welsh clung on but Johnny Leota's late try gave Samoa breathing space and a deserved victory.