Albion were beaten 3-2 by Watford in a pulsating Sky Bet Championship clash on Monday night.
The Hornets led at half-time thanks to Ken Sema’s close-ranger, yet Conor Townsend quickly equalised shortly into the second period.
Ismaila Sarr fired Watford ahead before Jed Wallace looked to have earned the Baggies a draw in a crazy, albeit entertaining, spell.
It wasn’t to be though, and Sema stole the points to move Watford up to fifth in the table and keep Carlos Corberán’s men 10th.
The boss named an unchanged team for the trip to Hertfordshire, sticking with the same XI and bench from the midweek draw against Blackburn Rovers.
They went behind midway through the first half when Sema struck home a rebound, the Watford player reacting quickest to convert a rebound after Keinan Davis’ initial shot was saved.
The hosts pressed for a second but found Josh Griffiths in their way when Keinan Davis’ low finish threatened to double their advantage.
Corberán made two changes at half-time, replacing Nathaniel Chalobah and Marc Albrighton with Jayson Molumby and Grady Diangana.
The switches seemed to inject some life into the visitors, Darnell Furlong and Brandon Thomas-Asante sending efforts over, and John Swift forcing a great save from Daniel Bachmann, in their quest for a leveller.
And they soon found the equaliser they deserved – Swift’s corner causing chaos and, eventually, Townsend brilliantly sending a deft volley home.
In a crazy spell straight after the goal, Watford almost immediately hit back through Sarr, the attacker smacking the post via a low drive.
Other than that, it was actually Albion who looked likelier to net again as Bachmann superbly saved Thomas-Asante’s diversion and Okay Yokuslu nodded narrowly off-target.
But in another twist Watford re-took the lead on 66 minutes, the ball falling fortuitously at the feet of Sarr, and the attacker making no mistake.
Albion then hit back once more – the home team getting caught playing out from a goal-kick, substitute Molumby winning possession and Wallace making it 2-2.
The game showed no signs of slowing down, Sarr seeing one disallowed for offside as the end-to-end clash continued, and it was now a matter of which club could find a winner.
Unfortunately Watford were the team to earn the victory, Sema’s strike deflecting off Erik Pieters and past Griffiths late on and claim them the points.
Albion Griffiths, Furlong, O’Shea, Pieters, Townsend; Yokuslu, Chalobah (Molumby 45); Swift (Grant 80), Wallace, Albrighton (Diangana 45); Thomas-Asante (Dike 62).
Substitutes: Button, Ajayi, Reach.