ALBION fell to a 1-0 defeat against Huddersfield Town at the John Smith's Stadium.
Rajiv van La Parra's 25-yard strike into the top corner on the stroke of half-time proved the difference between the two sides in Albion's first-ever Premier League meeting with the newly-promoted West Yorkshire outfit.
Town played the final 30 minutes with 10 men after centre-back Christopher Schindler saw red for a second bookable offence.
The Baggies pushed in search of a leveller, immediately making a triple attacking substitution, but they could not find the breakthrough - Salomon Rondon heading inches wide.
Albion will now look to get back on track after the forthcoming international break, with a home clash against Chelsea next up.
Town saw penalty appeals waved away after 15 minutes following Kieran Gibbs' challenge on Van La Parra, while Ben Foster got down to save comfortably from Tom Ince.
Schindler got across well to block Jay Rodriguez's strike after he had been played through by the recalled Hal Robson-Kanu in attack.
Ince blazed well over after the ball broke his way from a corner before he again tested Foster from distance, Rodriguez doing likewise at the other end.
Yet the Town breakthrough came just before the break.
Rodriguez appeared to be brought down on the halfway line but the free-kick went the way of the hosts, Aaron Mooy took it quickly and the ball eventually found its way to Van La Parra, who curled into the top corner from distance.
Town were reduced to 10 men in the 58th minute as Schindler saw red for a second booking.
And head coach Tony Pulis immediately made a triple substitution - introducing Rondon, Matt Phillips and James McClean.
Rondon headed narrowly wide in the 73rd minute as the Baggies pushed for an equaliser, before Terriers keeper Jonas Lossl pulled off two world-class saves to deny McClean and Phillips in added time.
But Albion could not find an equaliser as the Terriers claimed all three points in the first meeting between the two sides in seven years.
ALBION: Foster, Nyom, McAuley (McClean 59), Evans (c), Hegazi, Gibbs, Livermore, Krychowiak (Rondon 59), Barry, Rodriguez, Robson-Kanu (Phillips 59).
Subs: Myhill, Yacob, Brunt, McClean, Phillips, Chadli, Rondon.