Juan Mata scored a magical late free-kick as Manchester United beat a determined Watford 1-0 at Old Trafford to reignite their top four ambitions.
With seven minutes remaining, United were looking for inspiration after a lacklustre showing and their stand-in captain provided it, whipping home a pin-point free-kick from 25 yards.
Watford created and missed a number of excellent opportunities with Odion Ighalo the chief culprit - he is now without a goal in nine Premier League games.
The winning goal sent United level on points with Manchester City in fourth and 10 points behind league leaders Leicester City, although Manuel Pellegrini's men have a game in hand.
Timothy Fosu-Mensah, 18, was one of two changes made by Louis van Gaal as he became the third youngest player to start a Premier League game for United. He replaced Michael Carrick, who was rested, while Marcus Rashford continued up front after his double against Arsenal.
The young centre-half was given a real workout by a wily Troy Deeney but coped relatively well with his threat. If only his more experienced defensive team-mates followed suit.
Daley Blind played a dreadful ball out from the back on 18 minutes but Ighalo squandered the chance from 20 yards, firing straight at David de Gea.
Ighalo continued to cause the United back four problems but his lack of composure in front of goal meant Watford failed to capitalise. He latched onto a Deeney flick on 27 minutes and did brilliantly to work himself into space from 12 yards but skewed his effort wide of the post.
The chances kept falling to Watford's top scorer but he continued to wilt under pressure. He burst down the right after more sloppy defending by Blind but was denied by De Gea.
United continued to struggle to deal with Watford's aggressive game-plan and Guillermo Varela was the next man to present Ighalo with a wonderful chance on 38 minutes. His sloppy back pass was read by the Watford striker but again he fluffed his lines as De Gea stood strong.
United were non-existent as an attacking force in the opening 45 minutes and although the home crowd called for the intensity to increase, it was Watford that kept up the pace.
Etienne Capoue smashed an effort from 30 yards just over the bar before Sebastian Prodl had an effort cleared off the line by Rashford on 51 minutes.
Having weathered the relentless Watford storm, United finally got their attacking play going and Mata tested Heurelho Gomes on 60 minutes with a fierce drive that the goalkeeper punched clear.
Despite the increased tempo a goal never looked forthcoming and it was Watford - yet again - that created a glorious opening on 79 minutes. Ben Watson's corner was met five yards out by an onrushing Prodl but the defender somehow managed to head wide of the post.
Rarely do you get away with missing so many chances at Old Trafford and Watford were made to pay.
Anthony Martial was fouled about 25 yards from goal, which presented a chance for Mata to strike and he took full advantage, planting the ball perfectly into the top corner.
The relief around Old Trafford was clear to see. The top four march is on.
Player Ratings
Manchester United: De Gea (8), Varela (6), Blind (6), Rojo (6), Fosu-Mensah (7), Schneiderlin (6), Herrera (6); Martial (6), Mata (8), Memphis (6), Rashford (7).
Subs: McNair (6), Darmian (6), Lingard (6)
Watford: Gomes (6), Nyom (6), Britos (6), Prödl (5), Holebas (6), Capoue (7), Watson (8), Behrami (7), Abdi (7), Deeney (7), Ighalo (4).
Subs: Suarez (6), Anya (6), Amrabat (5)
Man of the match: Juan Mata