The strained look on the faces of Manchester United's embarrassed superstars spoke more eloquently than words could ever do as they made their silent exit from a self-inflicted beating at Fratton Park.

Merely being a member of United's all-star cast is a pressure in itself.

But this defeat has left them facing a Premiership title test-of-nerve.

Now just three points and a superior goal-difference separate them from Chelsea.

United, who face Watford in an FA Cup semi final on Saturday, have their next two league games at home against Sheffield United and Middlesbrough and manager Sir Alex Ferguson admits: "We have to make the most of that.

"But Chelsea have some tough games, too, in the last six and I can't believe somebody will not make them suffer as well."

Suffer? Stand-in skipper Rio Ferdinand's countenance after his amazing 88th-minute own-goal clinched the points for Portsmouth said it all.

So did the unmistakable look of boiling anguish in Wayne Rooney after he was rightly denied two penalty claims and wrongly robbed of a certain goal by an offside flag.

Rooney had to be physically restrained from approaching the official at the end of the game.

Ferguson said: "If it comes down to the last match of the season I will happily settle for that. To be fair to the lads, they have always shown character and I expect them to recover from this."

Matthew Taylor had put Portsmouth into a first-half lead, before Ferdinand's own goal doubled the home side's advantage.

United rallied, and John O'Shea pulled one back, but it was a case of too little too late with Pompey indebted to a number of classy saves from David James.

Portsmouth 2 Man Utd 1