Manchester - Manchester United slumped to a third successive Premier League defeat for the first time in 13 years as Jonas Olsson deflected in West Bromwich Albion's winner in their 1-0 victory at Old Trafford on Saturday.
United's latest lacklustre display means they have now failed to score in three consecutive league games for the first time since August 2007, statistics that hardly support manager Louis van Gaal's claim that his side will challenge for the title next season.
To make matters worse, 10 minutes after Chris Brunt's free-kick took a huge deflection off Olsson for the 64th minute decider, Robin van Persie wasted a 73rd minute penalty after Saido Berahino was ruled to have handled an Antonio Valencia cross just inside his area.
The Dutch forward's spot kick was saved superbly by Boaz Myhill, who dived low to his left to offer some sense of justice to Albion players who claimed Berahino had been outside the area.
United's defeat leaves them only four points ahead of fifth placed Liverpool with three games left in the race to qualify for the Champions League.
For Albion, their shock victory, achieved despite having only 20 percent of the possession, took them seven points clear of the relegation zone and should guarantee their survival.
Ashley Young appeared the best early prospect of ending United's goal drought as he probed down the left, cut in from his wing, reached the area and unleashed a powerful shot which deflected behind van Persie.
Van Persie, whose Old Trafford future is the subject of much debate, was appearing for the first time in two months and appeared ring rusty after his lay-off.
On 16 minutes he collected a short Ander Herrera pass and shot on the turn, an effort which Myhill could only parry behind at the expense of a corner from which van Persie was presented with another half-chance, this time hooking his effort directly at the visiting goalkeeper.
A few minutes after that attempt, Young was again the architect of a chance for van Persie, running with great purpose down the left and crossing to the corner of the six-yard area from where the striker shot into the side-netting.
Just before the half-time whistle, full-back Antonio Valencia burst into the area and drilled a low shot into the chest of Myhill, the ricochet flying to the edge of the area to Herrera who hurried the rebound high and wide of the Albion net.
And soon after the restart, Wayne Rooney, back in a deeper central midfield role, chanced his arm with a 20-yard effort that was far too close to Myhill.
When Daley Blind, playing as left-back, found himself in an advanced position soon after, a bit of urgency and a shot on goal was just what United needed.
But, unfortunately for the home supporters, his effort struck team mate Marouane Fellaini who was promptly flagged offside.
Albion offered little threat apart from a Joleon Lescott header directly at David de Gea and, early in the second half, Craig Gardner sent an 18-yard attempt flying off target.
Blind crossed low and dangerously into the six-yard area without any end product and Fellaini's lay-off allowed Herrera to side-foot an attempt wide from 18 yards as the home side finally discovered some tempo.
But that improvement had been found too late as Paddy McNair brought down Darren Fletcher 22 yards from goal, handing Brunt the free-kick from which he handed Albion a most unlikely lead as his shot struck the unknowing Olsson and changed direction dramatically on its way past de Gea.
The introduction of Angel di Maria improved United's fortunes and, in a late flurry, van Persie saw his 20-yard shot superbly saved by Myhill before his injury-time shot from even further out soared inches over the crossbar.