Albion, eighth, on 44 points with seven matches remaining
- Niang drills Hornets ahead from distance (13)
- Deeney prods home after restart (49)
- Britos sent off for second bookable offence (65)
- Attendance: 20,090
- Albion Star Man: Nacer Chadli
ALBION tasted defeat for the first time in three Premier League matches as they fell to a 2-0 reverse at 10-man Watford.
M'Baye Niang's thunderous 20-yard strike handed the Hornets an early advantage at Vicarage Road, Nacer Chadli coming close to an equaliser late in the first period when his free-kick clipped the outside of a post.
Troy Deeney doubled the home side's lead when he poked home shortly after the restart before a resurgent Albion were handed a route back into the game courtesy of Miguel Britos' dismissal for a second bookable offence.
Yet, despite applying plenty of second-half pressure, they could find no way through to taste defeat in Hertfordshire having taken four points from successive matches against Arsenal and Manchester United.
Southampton are next up at The Hawthorns on Saturday, with eighth-placed Albion on 44 points with seven matches of the campaign remaining.
Tony Pulis named an unchanged side from the starting XI who drew 0-0 at Old Trafford on Saturday although there was a place on the bench for fit-again Matt Phillips, who duly made his comeback from injury at half-time.
The visitors could have taken the lead after just seven minutes, Chadli played through by skipper Darren Fletcher but he was unable to to guide the ball home from a tight angle having seen his first effort rebound off Heurelho Gomes.
Yet it was the Hornets who took the lead after 13 minutes as Niang cut inside on the left and powered a strike beyond a helpless Ben Foster and into the far corner.
The home side went on to enjoy a period of dominance before Albion duly gained the upper hand as half-time approached, Chadli coming within inches of an equaliser when his 30-yard free-kick hit the woodwork.
Phillips replaced James McClean at the interval after five matches out with a hamstring strain. However, the Baggies found themselves 2-0 down within four minutes of the restart.
Niang's raking throughball split Jonny Evans and former Hornets man Allan Nyom and Deeney took a controlling touch before poking past the onrushing Foster.
Albion were not down and out, though, and - while introducing James Morrison and Salomon Rondon - pressed for a route back into the game, Chadli drilling wide.
Briton saw red in the 65th minute for his second booking of the game, holding back Rondon, and that spurred Albion further.
Rondon headed on to the roof of the net but Albion could not find a way back into the encounter.
Watford: Gomes, Cathcart, Prödl (Janmaat 45+3), Britos, Holebas, Doucouré, Cleverley, Capoue; Niang (Success 79), Amrabat (Mariappa 68), Deeney (c).
Subs: Pantilimon, Zúñiga, Okaka, D Pereira.
BOOKED: Britos (foul, 40), Niang (foul, 69)
SENT OFF: Britos (second bookable offence, 65)
Albion: Foster; Dawson, McAuley (Morrison 57), Evans, Nyom; Livermore (Rondon 62), Fletcher (c); Brunt, Chadli, McClean (Phillips 46); Robson-Kanu.
Subs: Myhill; Yacob, M Wilson, Field.
BOOKED: Robson-Kanu (foul, 43), McClean (foul, 45+6), Livermore (foul, 58), Nyom (foul, 83)
Referee: Paul Tierney (Lancashire)