ALBION secured a famous victory at Manchester United to make it back-to-back wins at Old Trafford for the first time since 1959.
Jonas Olsson was credited with the 63rd-minute winner after Chris Brunt’s drilled free-kick deflected off the back of his leg as he stood in the wall, wrong-footing United goalkeeper David De Gea.
But victory was only secured after the superb Boaz Myhill produced a marvellous parried save to keep out Robin van Persie’s penalty, given when Saido Berahino was adjudged to have handled inside the area soon after.
It secured an historic success against the most decorated club in English football - just a season after Berahino scored the winner in a 2-1 triumph on United soil.
Resilient Albion’s hard-working and organised approach paid dividends in front of the 75,454 present as they proved difficult to break down, epitomised by Claudio Yacob in the middle of the park.
Victory takes the Throstles on to the magical 40-point mark for this Barclays Premier League season and achieves the aim set out by head coach Tony Pulis when he took over the reins in early January.
Having kept an unchanged line-up for the last two games, Olsson and Youssouf Mulumbu returned to Pulis' starting XI from the side who held Liverpool to a goalless draw and triumphed over Crystal Palace.
The home support rose to their feet and chanted Rio Ferdinand’s name in the fifth minute of the encounter in memory of the former United defender’s late wife, who sadly passed away last night.
Ashley Young saw his shot deflected wide after 12 minutes before Joleon Lescott shrugged off his marker to send Craig Gardner’s corner straight into the hands of De Gea at the other end.
Myhill made two smart saves from Van Persie in a matter of minutes before sending another chance wide of the goalkeeper’s right-hand post from Young’s low cross.
In between those chances, Mulumbu sent another free header straight at De Gea, whose United side had won their last seven successive home matches.
Yet openings dried up after that as the remainder of the first half was largely played out in the middle of the park, Marouane Fellaini escaping punishment for a shove in the direction of Yacob’s face as the pair went to ground.
There was to be one more opening of sorts in first-half injury time as Antonio Valencia’s swerving drilled cross was parried by Myhill.
The Baggies stopper was again on hand to safely collect Wayne Rooney’s drilled strike minutes after the restart.
Gardner sent a long-range effort off target in the 54th minute before Van Persie’s tame hit was swallowed up by Myhill.
The deadlock was finally broken ten minutes later and it was Albion who struck.
Darren Fletcher, upon his return to Old Trafford, was fouled by Patrick McNair on the edge of the area. Brunt stepped and drilled the resulting free-kick which took a deflection off Olsson and left De Gea stranded.
Lescott escaped punishment as Juan Mata’s cross hit his arm in the penalty area but, soon after, the hosts were awarded a spot-kick as Saido Berahino was adjudged to have handled Valencia’s cross.
However, Myhill stepped up, dived low to his left and superbly parried Van Persie’s effort from 12 yards.
And it was the Baggies ‘keeper who preserved the visitors’ lead as he made brilliant saves from Van Persie and substitute Angel Di Maria – ensuring Albion tasted victory, their second successive triumph on the road in a matter of weeks.
Albion: Myhill, Dawson, McAuley, Olsson, Lescott, Brunt, Yacob, Gardner (Wisdom 89’), Mulumbu (Baird 76’), Fletcher, Berahino (Ideye 80’).
Subs: Rose, Sessegnon, McManaman, Anichebe.
GOAL: Olsson 63’
Man Utd: De Gea, Valencia, Smalling, McNair (Falcao 84’), Blind (Di Maria 63’), Mata, Herrera, Fellaini, Young, Rooney, van Persie.
Subs: Valdes, Blackett, Jones, Januzaj, Pereira.
SAVED PENALTY: Van Persie 74’
BOOKED: McNair (foul 62’)
Referee: Anthony Taylor (Cheshire)
Albion star man: Boaz Myhill