United has endured its worse home start in the top flight for 48 years, but finally secured three points at a ground that used to be such a fortress at the fifth attempt.

It needed some fortune to end a six-match run without a home victory that stretched back to last season, though, as referee David Coote overturned his decision to award struggling Albion a penalty at the start of the second half.

Fernandes breathed a sigh of relief after he had been adjudged to have brought down Conor Gallagher and the midfielder was a lucky man soon after when he was given a second chance to score from the spot.

Sam Johnstone tipped away Fernandes's first attempt after Darnell Furlong was harshly penalised for handball, but came off his line too soon, and the United talisman did not pass up another opportunity to open the scoring.

Johnstone made the first of several brilliant stops against his former club from an early Anthony Martial header and produced a superb reflex save low to his left to thwart the United forward soon afterwards.

The Baggies had a first sight of goal when Karlan Grant's shot was tipped wide by David de Gea before Martial was denied a penalty when the France international felt he was tugged back by Matheus Pereira.

Albion thought it had a golden opportunity to take the lead just after the break and Coute's pitchside change of heart – which preceded an excellent De Gea stop from Conor Townsend – was not the end of the VAR )video assistant referee) drama.

Johnstone was shown to be too quick off the mark and Fernandes made no mistake second time around.

Substitute Callum Robinson struck the bar just after coming on and Johnstone produced another sharp save to prevent Marcus Rashford from doubling United's lead.

The Baggies' wait for a win goes on, while United, which was without Paul Pogba because of a knock, is up to ninth on the table.