Swansea stunned Manchester United 2-1 Sunday, with Andre Ayew and Bafetimbi Gomis leading a fight-back to see off the English giants. Juan Mata had given United a second-half lead, but Swansea exploited United's poor defense and ball control in midfield to strike back immediately and secure all three points. The result lifted the Welsh side up to fourth place in the table, and kept United five points off the lead set by their cross-town rivals Manchester City.

It was an entertaining match that capped a frenetic weekend in England ahead of the international break, but the result will deepen the worries that surround United. Wayne Rooney, so impressive midweek in Belgium, was again absent on the day, and United's control of the ball in the middle of the field continued to be sub-par.

More worrying long-term is United's situation between the pipes: with David de Gea widely expected to join Real Madrid before the Tuesday deadline, United do not seem to have a capable backup in Sergio Romero. Culpable on both Swansea goals, it is hard to see him being a long-term solution. Transfer deadline day now looks as if it might be extremely interesting at Old Trafford.

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It should be noted that the Swans, under manager Garry Monk, have been a tricky side for Louis van Gaal's men: they'd won three of their last four games over the Red Devils across all play and last year beat them both home and away in the league. They have now beat them in three games straight.

Both teams shuffled their lineups, but only slightly: Jefferson Montero was ruled out with a thigh injury pre-game, denying Swansea of one of their best attacking options. And United made two changes from the side that swept aside Brugge midweek in the Champions League, with Bastian Schweinsteiger and Morgan Schneiderlin returning in place of Adnan Januzaj and Michael Carrick.

The switch worked, for a time: United had Swansea on their heels almost from the start, with Memphis Depay forcing Lukas Fabianski into a sprawling save in the second minute, curling his free-kick around the wall and nearly finding the inside of the post. Juan Mata also had a fine look twenty minutes in off a little dink from Ander Herrera but he was only able to find the side of the net.

But Swansea grew into the game, and the early dominance of Depay up top and Schweinsteiger in his sweeping role faded as Gomis and Jonjo Shelvey started to combine down the gut. Rooney barely touched the ball in the first half and was little better in the second.

A foul on Ayew 25 minutes in started a sustained flurry of pressure on Romero, with Shelvey whipping in a low cutter that Gomis tipped on to Gylfi Sigurdsson. Sigurdsson took a blind hack at it and was astonished to see it just creep wide of the far post. That near-miss shook Swansea to life, and they nearly punished United a minute later when Romero, attempting to put the ball back into play, instead passed the ball right to Shelvey just outside the area. Shelvey tried to chip the keeper and the Argentine was lucky to scramble back and recover.

Gomis then had perhaps the best chance of the game at the half-hour. Storming through the middle of the pack, Gomis juked around Daley Blind, caught Chris Smalling going the wrong way, then rocked a shot past Romero to the far post. Agonizingly, the ball instead hit the outside of the post and ricocheted back out, leaving Gomis pounding the turf in frustration.

United would only have one other look in the half, with Herrera coming close to Fabianski's net off service from Schneiderlin. But after the break, Mata finally struck. Ayew was left chasing Luke Shaw after a ball bobbled up at midfield Shaw fired in a cross that Rooney appeared to deflect on to Mata, lurking at the far post with only Ashley Williams to beat. With the keeper flying down, Mata roofed the ball to break the deadlock.

Monk had seen enough, and quickly yanked Wayne Routledge with Ki Sung-Yeung, shifting to a 4-3-2-1 that compressed the width of the field. That paid almost immediate dividends as, on the hour, Williams latched onto a loose ball conceded by Rooney, and pounded the ball 40 yards down the field to Sigurdsson. Ayew was waiting unmarked near the penalty spot to head the ball down into the turf and past Romero.

Just five minutes later, United's defense was caught out again on a simple play: another loose ball was coughed up on the halfway line, Ayew was fed the ball out wide, and he sent in a long cross that bent around the back line for Gomis to run on to and score with ease. Romero looked very shabby on the goal, unable to keep out what was a fairly routine shot at his near post but the initial defending on the cross in was just as poor.

Van Gaal's reaction was perplexing: he yanked Mata and Schneiderlin to put on Marouane Fellani, operating as a front-running target man for the final 15 minutes. It worked as well as you might expect, which is, not at all.