This is threatening to become a season in hell for David Moyes and his Manchester United side. There is still a second leg to come of this semi-final so they are not dead yet and could still reverse their fortunes to reach Wembley.
Moyes thought that the Fabio Borini penalty that sent United on a long journey home was dubious, given that Adam Johnson appeared to take a theatrical tumble to earn it, but the bottom line is that his team are finding ways to lose games they once won.
The victorious Sunderland manager, Gus Poyet, is conscious that it is only half a job done. "It was a very tight game, and sometimes a decision goes for you and you win the game," he said. "We know it's not easy to beat Manchester United but now we go to Old Trafford with a lead."
Yet the second leg in a fortnight's time could bring more misery for Moyes and his men as the four home defeats in four weeks – to make five altogether this season – mean Old Trafford is no longer the fortress it was.
Although a resounding win was the order of the day for United the avoidance of defeat was the first priority. To lose a third match in succession, for the first time since the end of the 2000-01 season when the title had already been won, was the doomsday scenario the champions could not contemplate as they sought to deal with the demons that had swarmed into their minds during the previous two losses.
The one thing United knew was that Poyet would remind his side that their opponents were vulnerable and that they should get at them from the start.
A glimpse of this came when Sunderland forced an early free-kick down the right but Sebastian Larsson's delivery was not up to standard. Then, after a Borini shot went wide following Steven Fletcher's lay-off, the host's pressing continued. Larsson's attempt was blocked by Jonny Evans following a clearing header from Nemanja Vidic.
The team Moyes selected featured only four survivors from the XI who started the FA Cup defeat to Swansea at the weekend. Evans, Antonio Valencia, Tom Cleverley and Danny Welbeck all retained their places, with Wayne Rooney and Robin van Persie still absent with injury.
The disjointed nature of previous defeats was visible again here as Ryan Giggs gave possession away too easily and the lone striker, Welbeck, appeared isolated. It was Giggs, though, who smacked Vito Mannone's crossbar with a deflected effort from 25 yards as the half-hour approached and United began to assert themselves.
Although the rumblings of discontent from some fans grows louder, the hardcore of away support sang their "Come on Davey Moyes" song despite the average fare they witnessed during the opening period and beyond. Adnan Januzaj did his best to improve their evening when he took advantage of space created by a Patrice Evra run to smoothly switch the ball from his left foot to the right before curling in a shot that was blocked by Phil Bardsley.
When Rooney and Van Persie are not playing United have the feel of what they currently are: a side of mid-table strugglers. Januzaj is the exception and it was the 18-year-old who had Mannone beaten as the break neared but the strike was correctly ruled offside.
United had limited Sunderland to just a single shot on target before disaster struck on the stroke of half-time. This time Larsson recalibrated his radar to swing in a precise free-kick from the right that Wes Brown, beyond the far post, turned back across goal. Giggs and Bardsley slid in, with the United man winning the race but not preventing a goal.
Moyes sent out his players early for the restart and they were soon camped near Mannone's goal as first Welbeck, then Evra, tried but failed to test the keeper. It was Vidic who dragged United back into the tie, rising to head a Cleverley corner for an equaliser that the sent the vocal travelling support wild.
Yet when Borini raced down the left before missing narrowly to David De Gea's right, an alarm sounded that became louder when Larsson was allowed space to fire at the Spaniard, who made a fine save. Now came Cleverley's intervention, the midfielder clipping Adam Johnson, just on as a substitute, which persuaded Andre Marriner to give the penalty. Marginal or not, Borini made no mistake from the spot.
United ended the match bombarding the Sunderland goal but, not for the first time, they lacked the decisive touch. Next up on Saturday is another meeting with Swansea. United – and Moyes – can hardly stomach more despair.