Tony Pulis accused Alexis Sanchez of cheating after Albion's controversial 2-0 defeat against Arsenal.
The Baggies were behind in the 20th minute when Ben Foster could only palm Sanchez free kick into the path of Alexandre Lacazette, who nodded in from close range.
But it was Albion's appeals for a penalty in the 7th minute that angered Pulis. Baggies front man Jay Rodriguez was clearly tripped by Arsenal defender Shkodran Mustafi tripped the striker.
Rodriguez regained his footing and fired against the post before Jake Livermore fired wide. However, Pulis believes the intitial offence should've been picked up by referee Bobby Madley.
"In the game's first free-kick Sanchez dives and should be booked. That's cheating," Pulis told Sky Sports.
"Then the tackle in the box on Jay, it is a stonewall penalty."
"We tell our players not to roll about. He still wanted to score but once he has missed the referee should pull it back. It could be a penalty and they could have a player sent off, so we not only score but are against a team down to 10 players.
"We have got to start taking chances. We have given Arsenal a good game, but we had to chase it in the second half and that suited Arsenal."
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