Alan Pardew is expected to be shown the Hawthorns exit door after his Baggies side lost a fifth consecutive game.
One-time Albion target Troy Deeney scored the only goal of the game when he gave Watford the lead in the 77th minute following a midfield mix up.
The Baggies had their chances with Salomon Rondon again firing a blank in front of goal as Albion's woes in front of goal continue.
Another defeat for Pardew leaves Albion eight points away from safety and stretches his run to only one win in 14 league games.
"It’s hard to stand in front of the players when they deserve something from the game and they’ve given me everything," said the under-fire boss.
“Unfortunately we fell short in the scoring area.
“We had chances again today but we didn’t take them.
“We couldn’t get ourselves a goal today.
“We came close but not close enough.
“We then make one mistake and we get punished. Unfortunately that’s our season at the moment.
“We’ve got to keep going. There’s nothing else to do.
“I’d like to thank our fans. I thought they were incredible today.”