United got back to winning ways in the league with a patient performance against a resolute but limited Albion side whom were unable to repeat their previous two smash and grabs at Old Trafford.
After long spells of fruitless first half pressure, the breakthrough finally came seven minutes after half-time when Jesse Lingard fired home his first for the club before Juan Mata's late penalty sealed victory for Louis van Gaal's side.
The Reds started brightly and went close after 15 minutes, when Bastian Schweinsteiger picked out Wayne Rooney whom in turn found Mata and the Spaniard curled his effort narrowly wide.
West Brom, whom fielded former United duo Jonny Evans and Darren Fletcher, defended tirelessly and were happy to sit back and soak up the pressure.
Despite the dominance in possession, nothing clear cut came United's way but Lingard went close when Mata's perfectly weighted pass almost picked out the onrushing winger, only for Craig Dawson to recover well and clear.
The young winger was then put through by Anthony Martial but Evans did well to clear, before Martial himself was thwarted by a smart stop from Baggies keeper Boaz Myhill.
Lifted by the now customary chants of 'attack, attack, attack' after half-time, it was not long before the Reds finally turned possession into tangible advantage and, fittingly, it was the excellent Lingard whom broke the deadlock.
With 52 minutes on the clock, Martial sent over a cross looking for Wayne Rooney and Chris Brunt's clearance fell only as far as Lingard who took a touch and curled a superb strike past the despairing Myhill.
The Warrington born winger's expertly taken goal belied his 22 years and lifted a jubilant Stretford End stirred from a first half slumber.
Now 1-0 down, West Brom had no option but to finally come out and attack, and this they did as Evans almost seized on defensive uncertainty possibly brought about the height and power of Baggies substitute Saido Berahino.
Van Gaal's side were beginning to live dangerously and it was Berahino whom next went close when he should have done better from point-blank range but could only nod over the bar when left unmarked.
In a proud moment soon after, 18-year-old Academy graduate Cameron Borthwick-Jackson came on for a 14 minute cameo at left-back and did not look out of place with some neat touches and confident tackles.
Albion did not threaten thereafter, though, and United made the game safe when Gareth McAuley scythed down Martial and subsequently saw red to ensure Albion would finish the match with ten men.
Mata rolled home the spot-kick to seal victory and a fifth clean sheet on the bounce as United moved to within one point of leaders City at the top.
Overall team performance: 7.5/10
United Faithful man of the match: Jesse Lingard