(CNN) -- FA Cup holders Portsmouth suffered the indignity of a fourth round exit to lower league opposition as Swansea City beat the Premier League strugglers 2-0 at Fratton Park on Saturday.
Swansea players celebrate their 2-0 upset victory over holders Portsmouth at Fratton Park.
Portsmouth, who won the oldest cup competition last season under former manager Harry Redknapp, showed little of that form as they went out to the second-flight team from Wales.
In the late kickoff, Manchester United came from a goal down to beat Redknapp's current charges Tottenham Hotspur 2-1 at Old Trafford.
Roman Pavyluchenko put Spurs ahead with a neat fifth minute header to reward a fine start by the visitors.
But United struck back with two goals in three minutes just after the half hour mark as first Paul Scholes scored with a deflected effort and former Tottenham striker Dimitar Berbatov struck after a superb pass by another ex-White Hart Lane favorite Michael Carrick.
The win leaves Premier League United still on course for an unlikely quadruple and they will face Tottenham again in the final of the League Cup on March 1.
On a day which promised shocks, Chelsea saw Ipswich equalize at Stamford Bridge before recording a 3-1 victory with Michael Ballack and Frank Lampard scoring.
West London neighbors Fulham were tied 2-2 at non-league Kettering before winning 4-2.
Andy Johnson and Bobby Zamora scored late for the Premier League team to spare their blushes.
The other non-league side in the fourth round, Torquay, were beaten 2-0 at home by Coventry.
Burnley, beaten in heart breaking fashion by Tottenham in the semifinals of the League Cup in midweek, had some consolation with a 2-2 draw at West Bromwich Albion.
Other Premier League teams had easier passages with Middlesbrough beating second-flight leaders Wolves 2-1 and West Ham accounting for Hartlepool 2-0 in the early kickoff.
Hull beat Millwall by the same score, Sunderland and Blackburn were scoreless in an all-Premier League tie, while high-flyers Aston Villa battled to a goalless draw at Doncaster.
But it was defeat for Portsmouth which captured the headlines and continued their lackluster run under new manager Tony Adams.
Championship side Swansea took a 27th minute lead as Jason Scotland played a high through ball for on-loan Nathan Dyer to beat David James with a fine strike.
Scotland, excellent throughout, put Swansea two up just before the break by converting a disputed penalty.
Portsmouth turned up the pressure in the second half but found visiting keeper Dimitrios Konstantopoulos in fine form.
He made some key saves but could only watch as England international striker Peter Crouch struck the woodwork with a late effort.
Last-ditch defendiing kept Swansea in front in the closing moments as they completed a famous victory.