Pundit is tipping Newcastle to slip to another defeat.
Newcastle lost 3-0 at home to Watford and now travel to The Hawthorns this evening.
Newcastle have looked impressive defensively this season but this fell apart on Saturday against Marco Silva's Hornets.
Merson believes Newcastle could have shipped as many as eight goals, and has little confidence in them pulling off an away win.
"I am not exaggerating, Watford could have won 8-0! Newcastle are all over the place and I am going to go 2-0 to West Brom."
Merson has routinely tipped Newcastle for defeats this season, and they have been proving him correct of late.
They have now slipped out of the top 10 into 14th place, just four points above the relegation zone.
West Brom are in 17th, three points behind Newcastle, and can bring themselves level with Rafa Benitez's side with a midweek victory.