Tony Pulis admitted it was a case of deju vu after Albion conceeded a late goal to lose 1-0 at Arsenal.
The Baggies had defended resoultely for 86 minutes before Oliver Giroud's late header.
It was the second time in a month Albion had visited the capital and played well but ended up on the losing side after the Baggies' visit to Chelsea on 11th December.
"It is hard to take. The players worked so hard. Arsenal are a good team and had lots of chances but to concede so late is disappointing," said Pulis.
"Olivier Giroud just outmuscled Gareth McAuley out of the way.
"Gareth said Giroud grabbed his shirt before the ball came over - I'm not sure if he did."
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