Manchester United remain five points adrift of the Premier League leaders, Manchester City, after Javier Hernandez's early goal gave them victory over Swansea at the Liberty Stadium.
The Mexico international struck in the 11th minute, sliding home his fifth goal of the season from Ryan Giggs' pass after Angel Rangel had carelessly given away the ball on the edge of his own box, to give United their first win at Swansea at the ninth attempt.
Scott Sinclair missed the home side's best chance when he miscued with an empty goal at his mercy, but, although they had the better of the play in the second half, the Welsh side struggled to create against a well-organised United rearguard as they suffered a first home defeat of the campaign.
Former Wales international Giggs made his return from a hamstring injury as United made their first trip to Swansea since 1982.
Sir Alex Ferguson, the United manager, also restored goalkeeper David De Gea to his starting XI in place of Anders Lindegaard, while Michael Carrick was handed a place in midfield.
Danny Welbeck was absent due to a muscle strain but the visitors, who started the game eight points behind league leaders Manchester City, still had the threatening partnership of Javier Hernandez and Wayne Rooney to call on in attack.
Swansea manager Brendan Rodgers restored Scott Sinclair to the left wing with Wayne Routledge moving to the centre of midfield as a calf problem limited Joe Allen to a place on the bench.
Nathan Dyer and Sinclair both made encouraging early bursts down the flanks, and Mark Gower volleyed wide after Patrice Evra failed to clear a Rangel cross.
But Swansea's promising start was undone in the 11th minute when Hernandez struck.
The goal briefly rocked the hosts back on their heels but a wonderful jinking run from Dyer, which saw the winger beat Rooney, Giggs and Evra along the way, soon had the home crowd on their feet.
Swansea started the second half with more verve and vigour and it took a brave defensive block from Nemanja Vidic to prevent Ashley Williams getting on the end of Garry Monk's goalbound header.
Swansea were enjoying their best spell of the game and more good work from Sinclair, who was enjoying the better of his tussle with Phil Jones, forced Rio Ferdinand to head behind under pressure from Dyer. But, having survived, United took a stranglehold on possession.
Rooney had a chance to cap his fine individual display late on but chipped over the bar after getting a lucky ricochet from a Williams block, before Jones clipped the post and Nani fired wide as time ran out.