Huddersfield Town remain deep in Championship relegation trouble after John Swift's penalty earned Carlos Corberan's West Bromwich Albion victory against his former side.
The Baggies went in front on the half-hour mark when Conor Townsend was bundled over in the box by Matty Pearson.
Swift slotted home from the spot and the hosts had further chances to stretch their lead in a dominant first half.
Neil Warnock's men created a few openings in the second half but West Brom goalkeeper Josh Griffiths was largely untroubled throughout.
The game was West Brom manager Corberan's first league match against Huddersfield since leaving the club at the end of last season after taking them to the play-off final.