ALBION fell to a 4-0 defeat against Premier League champions Chelsea at The Hawthorns.
Two goals inside six first-half minutes from Alvaro Morata and Eden Hazard put the Blues in command before Marcos Alonso added a third just before half-time.
Hazard added his second of the match just after the hour as Chelsea claimed the spoils.
Head coach Tony Pulis made two changes for Albion's return to action following the November international break, recalling Matt Phillips and Salomon Rondon.
And it was Rondon who had the ball in the net after just five minutes as the Baggies started brightly, only for the Venezuela international to see his header ruled out for offside.
Gareth McAuley did superbly to get a touch on Tiemoue Bakayoko's clear strike at goal but it was the visitors who opened the scoring in the 17th minute.
Hazard shrugged off a knock to his ankle and unleased a powerful low strike from 25 yards which was parried by Ben Foster and Morata reacted quickest to fire home the rebound.
It was soon 2-0 as Cesc Fabregas found Morata, whose exqusite flick sent clear Hazard and he rounded the onrushing Foster to slot home into an empty net.
Albion found themselves further behind at the break after Alonso volleyed Fabregas' deep free-kick into the roof of the net from the far post.
Claudio Yacob was introduced at the interval as Albion rallied, starting the second period in similar fashion to the way they opened the first.
But Hazard extinguished any hopes of a fightback when he latched on to Fabregas' long throughball to add a fourth in the 62nd minute.
Oliver Burke made his long-awaited return from injury with 20 minutes remaining with James McClean also entering the fray.
And the latter spurned Albion's best chance of the game in the closing stages, dragging a shot wide after finding himself one-on-one with Courtois.
It was to be the last action of the game as Chelsea left The Hawthorns with all three points.
ALBION: Foster, Phillips (McClean 84), McAuley, Evans (c), Hegazi, Gibbs, Livermore, Barry, Krychowiak (Yacob 45), Rodriguez (Burke 70), Rondon.
Subs: Myhill, Nyom, Brunt, Robson-Kanu.