United slipped to a third consecutive league defeat as we were somehow denied victory by a string of outstanding saves from West Brom keeper Boaz Myhill.
The thrilling, high octane wins over Tottenham, Liverpool and Manchester City are now nothing but cherished memories and any momentum built by those victories have now come to a worryingly profligate end.
The Reds remain in fourth place, but are once again glancing nervously over our shoulders as fifth placed Liverpool moved to within four points of us with victory over QPR.
Any hopes of a top three finish are now surely over (Arsenal have two games in hand) but the equation remains the same: two wins from the remaining three games will secure a return to the Champions League.
United boasted 80% possession and quite simply battered the visitors but once again lacked a cutting edge against a limited but well organised West Brom side who, to their credit, defended magnificently.
At times this match was Robin van Persie against Myhill, as the Baggies stand in keeper stopped everything we threw at him, and Tony Pulis' side ultimately nicked an incredible smash and grab victory through Chris Brunt's deflected second half free-kick.
Myhill denied Van Persie early on, Ashley Young's well-struck drive went behind off Craig Gardner, and RVP again went close when he lashed wide from Marouane Fellaini's pull back.
United had a penalty appeal turned down when Fellaini was felled by Gardner, before Albion went ahead in fortuitous fashion on 63 minutes.
Brunt's 25 yard free-kick, which probably would have been saved by David de Gea, flew into the wall, struck the unaware Jonas Olsson on the leg and deflected in.
The Reds laid siege to the Albion goal and were given a helping hand, quite literally, when Saido Berahino handled Antonio Valencia's cross and a penalty was awarded.
The contact with the ball looked to perhaps be outside the area, but it proved irrelevant as Myhill once more denied our Dutch striker with a good save down to his left.
Paddy McNair headed wide, Fellaini's header was cleared after a scramble, Juan Mata went close on the angle and Myhill produced two more brilliant saves to keep out Angel Di Maria's dipping drive before reacting smartly to superbly tip Van Persie's effort around the post.
It was just one of those days for this United side, who for the third successive match were beaten in a similar fashion: frustrated by the opposition, hit on the counter and unable to find a way back.
Overall team performance: 8/10
United Faithful Man of the Match: Robin van Persie