Anwar El Ghazi netted twice at The Hawthorns as Aston Villa handed Sam Allardyce a 3-0 defeat in his first match as West Bromwich Albion head coach.
Allardyce, taking charge of his eighth Premier League club, saw his West Brom team go behind in the fifth minute when El Ghazi converted Bertrand Traore's cross.
The Baggies were reduced to 10 men on 36 minutes when Jake Livermore was sent off for a challenge on Jack Grealish, after referee Martin Atkinson used the Referee Review Area.
Ollie Watkins had a goal ruled out for offside and El Ghazi was thwarted by a smart stop by Sam Johnstone as Villa pushed on in search of a second goal.
Their pressure paid off with six minutes remaining, thanks to a delightful finish by Traore from Grealish's pass.
El Ghazi added his second and Villa's third with an 88th-minute penalty, after Grealish was fouled by Semi Ajayi.
The win moves Dean Smith's side up to ninth on 22 points. West Brom remain in 19th place on seven points.
See: West Brom report | Aston Villa report
Next fixtures
West Brom: 27 Dec v Liverpool (A)
Aston Villa: 26 Dec v Crystal Palace (H)
Referee: Martin Atkinson. Assistants: Lee Betts, Constantine Hatzidakis. Fourth official: Robert Jones. VAR: Darren England. Assistant VAR: Stephen Child.
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