ALBION were left to feel hard done by as they came away from the Emirates Stadium on the end of a 2-0 defeat to Arsenal.
The Baggies saw loud penalty appeals waved away early on after Shkodran Mustafi appeared to clip Jay Rodriguez, who subsequently picked himself and struck a post before later seeing a goalbound header hooked off the line.
It was Alexandre Lacazette who did the damage for the Gunners, nodding home from close range midway through the first period, before slotting home a second-half spot-kick.
It came on a night when Gareth Barry broke the all-time Premier League appearances record, with the midfielder handed the Albion captaincy for what was his 633rd top-flight outing.
The Baggies now head into Saturday's home encounter against Watford on eight points from their opening six matches of the campaign.
Tony Pulis, who became the first Albion boss to take charge of 100 Premier League matches, made three changes from the Carabao Cup defeat to Manchester City - Barry, Ahmed Hegazi and Jake Livermore replacing Claudio Yacob, Gareth McAuley and James Morrison.
Alexis sent a free-kick narrowly wide in the early minutes before Rodriguez was at the heart of the action as referee Bobby Madley waved away penalty appeals.
The forward used his pace to burst past Mustafi into the area, cut inside and appeared to be brought down by the Gunners defender - Rodriguez quickly stood up and subsequently saw his shot tipped on to the far post by Petr Cech while Livermore could not convert the rebound.
And, following that frustration, Albion found themselves 1-0 down shortly afterwards.
Ben Foster did well to tip Alexis' free-kick on to the crossbar but Lacazette was first to react and head home from close range.
The Baggies deserved to be level and almost got their just rewards before the interval.
Firstly, Rodriguez beat Cech with a header only for the ball to be hooked off the line by Nacho Monreal before the summer signing was inches away from connecting with Hal Robson-Kanu's effort across the face of goal.
Lacazette saw an effort deflected narrowly over as the first 15 minutes of the second period flowed from end to end.
Yet the Baggies were left to rue what might have been as Allan Nyom was adjudged to have cut off Aaron Ramsey in the box and Lacazette slotted home the subsequent spot-kick.
ALBION: Foster, Nyom (Phillips 74), Dawson, Evans, Hegazi, Gibbs, Livermore (Morrison 62), Barry (c), Krychowiak, Robson-Kanu (Rondon 63), Rodriguez.
Subs: Myhill, Yacob, Brunt, McClean.