Deehan had been warned by a female police officer earlier in the match to remain in his dugout. He was escorted from the ground shortly after the sending-off of the United player Petr Katchouro.
"I'm delighted with the win but horrified that my assistant manager is down at the police station," United's manager, Steve Bruce, said. "I've got to go and see the police now but it leaves a sour taste in the mouth. He has been arrested seemingly for swearing but there were thousands of people swearing out there today."
A spokeswoman for Scotland Yard confirmed: "A 41-year-old man has been arrested during the game at Loftus Road for using threatening words and behaviour. He is still being held in custody at Hammersmith Police Station."
Bruce was no happier at the decision to send Kachuro off after a clash with Richard Langley 16 minutes from the end. "We'll all have to look at the incident because I know Petr would never throw an elbow," he said. "He was trying to shield the player away with his arms."
Kachuro had virtually wrapped up the points for the Blades after half an hour by adding to Graham Stuart's close-range opener, and even after the Belarussian was sent off QPR could not add to Gavin Peacock's 49th- minute penalty.
Ashley Ward, the striker coveted by Nottingham Forest and Leicester City and priced by Barnsley at pounds 5m, exhibited the full range of his repertoire in five extraordinary first-half minutes at the Stadium of Light as the Tykes ended the 18-match unbeaten start to the season made by Sunderland, the Nationwide First Division leaders, with a 3-2 win.
Ward's dramatic cameo began in the 33rd minute when he capitalised on a mix-up between Thomas Sorensen and Darren Williams to tap in his 14th goal of the season. Three minutes later Williams felled Bruce Dyer and Ward blasted the penalty over the bar. A minute later he kicked Williams off the ball and, for the second time in three games, was sent off.
His remaining 10 colleagues held out for the rest of the half and increased their lead in the first minute of the second half, Dyer scoring. The Wearsiders seemed to have salvaged a point with a Martin Scott penalty and Niall Quinn's equaliser.
"At that stage I thought we were going to win," Peter Reid, the Sunderland manager, said. But they slumped to their first home defeat in 14 months when Kevin Ball fouled Sean McClare and Darren Barnard tucked in the late penalty.
High-flying Ipswich also slipped up at home when Bob Taylor's 90th-minute goal gave Bolton a 1-0 win. George Burley, the Ipswich manager, blamed the inadequate size of his squad. Norwich moved up to fifth by beating Tranmere Rovers 3-1 at Prenton Park. "It was an early Christmas present for Norwich," John Aldridge, the Tranmere manager, said.
Lee Hughes, the division's leading scorer, took just 48 seconds to score his 28th goal in 26 games for West Bromwich Albion, giving them the lead against Portsmouth at Fratton Park. Thereafter, he was upstaged by Pompey's 17-year-old substitute Luke Nightingale, who scored twice to keep the points on the South Coast.Reuse content