JOSEPH-DESIRE Job deepened Sir Alex Ferguson's despair as Middlesbrough celebrated another famous Old Trafford victory.

On the day Irish racing magnates John Magnier and JP McManus increased their stake in Manchester United to 28.89 per cent and edged towards the 30 per cent threshold which forces them to launch a takeover bid, Ferguson's side lost vital ground to Arsenal in the Premiership title race.

With Magnier and Ferguson still embroiled in a bitter legal feud over the stud rights to racehorse Rock of Gibraltar, the stock market development had already turned up the heat on the United boss.

And Boro piled on the agony as they surged into the lead through two rare headed goals from the diminutive Juninho.

The Brazilian struck first in the 34th minute when left-back Franck Queudrue's long-range effort was touched on to the bar by goalkeeper Tim Howard and Juninho darted in to nod home the loose ball.

And when Boro won a corner on the right four minutes later, Stewart Downing played it short to Gaizka Mendieta and the Spaniard's cross to the near post was glanced in by Juninho for his eighth goal of the season.

But United hit back on the stroke of half-time, Louis Saha chesting down Ryan Giggs' centre and Ruud van Nistelrooy lashing home a half-volley.

Giggs levelled in the 63rd minute, bundling the ball in from close range after his initial effort had come back off Boro right-back Danny Mills.

But Job restored Boro's lead ten minutes from time with his fifth goal this term when he took delivery of Doriva's pass to turn quickly and fire into the far corner.

And in a sensational conclusion, former Boro target Diego Forlan, a late substitute for Nicky Butt, headed against the bar with the goal gaping in front of him.

Old Trafford has been something of a happy hunting ground for Boro in recent years - this was their third win here in six Premiership visits.

They were clearly further emboldened from the start by manager Steve McClaren's record against mentor Ferguson.

McClaren, Ferguson's former right-hand man, now boasts four victories in seven meetings between them in League and Cup.

The defeat, only United's second at home this season, leaves them five points behind Arsenal and facing a major test of their resolve.

McClaren axed club record £8.15m buy Massimo Maccarone and recalled the in-form Job to spearhead the attack as Boro attempted to throw off the listlessness of Saturday's gut-wrenching home defeat by Blackburn.

Winger Downing, a young colt being groomed for stardom from Boro's own stable, was also brought back into midfield in place of Stuart Parnaby, which meant Bolo Zenden switched into the middle alongside Doriva.

United were without the steely midfield influence of skipper Roy Keane, but were able to call on Butt, who Boro would dearly love to have in their ranks.

United threatened first when Giggs emerged unmarked on the left to drill a near-post drive which keeper Mark Schwarzer managed to divert wide.

But Boro weren't fazed and Juninho caused panic in the home defence when he burst into the area and forced Howard to scamper across goal and save at his feet.

In Boro's next move, Job went down in the box wide on the left under the challenge of Howard and McClaren leapt from the dug-out to demand a penalty after referee Paul Durkin waved aside appeals.

Queudrue then headed wide from Downing's left-wing corner as Boro continued to rattle the Red Devils.

But it needed a superb saving tackle from skipper Gareth Southgate to deny Giggs just as he was about to shoot in front of goal in the 19th minute to keep the scoresheet blank.

Boro were in dreamland after Juninho's quick-fire double, but van Nistelrooy's 22nd goal of the season threw the game back into the melting pot.

Quinton Fortune, who claimed the only goal in the sides' Christmas clash at the Riverside when his shot was deflected in off Mills, wasn't so fortunate last night with a drive that struck Mendieta and flew wide.

But Schwarzer had to be at his best when, from the resultant corner by Kleberson, Mikael Silvestre connected with a downward header which the keeper blocked before the ball was scrambled behind.

Mills, who had already been booked, risked further punishment after being forced off for treatment.

Boro were desperate to get Mills back on the field and he raced down the touchline to remonstrate with the fourth official, who was then grabbed by an equally irate McClaren as Mr Durkin continued to ignore the visitors' pleas.

Giggs' goal was a bodyblow to Boro and they should have been trailing when John O'Shea's point-blank shot on the end of van Nistelrooy's knockdown was deflected over.

But everyone had reckoned without the predatory touch of Job.

Result: Manchester United 2 Middlesbrough 3.

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