Brian Deane, the England striker who was returning after suspension, made amends for two glaring misses by scoring his 17th goal of the season to edge United in front with a quarter of an hour remaining.
Coventry took a first-half lead through John Williams and were not pegged back until Dane Whitehouse equalised in the 69th minute.
The Blades enjoyed a slice of luck when Brian Borrows struck a penalty against the crossbar with 10 minutes to go, and rubbed salt into Coventry's wounds when the substitute, Adrian Littlejohn, lobbed Steve Ogrizovic for their third six minutes later.
The result completed a bad night for Coventry who could not field their new pounds 1.5m striker Roy Wegerle because a medical hitch had held up Kevin Gallacher's move in the opposite direction to Blackburn.
Rovers put last week's cup disappointments behind them with a 3-0 victory over a sloppy Queen's Park Rangers at Loftus Road courtesy of goals from Stuart Ripley, Kevin Moran and Mark Atkins.
Ipswich's decline continued with a 3-0 trouncing at Everton pushed them down to 14th in the table, 10 places below their position just over a month ago. Stuart Barlow volleyed a spectacular opener from 20 yards after 18 minutes, and Matt Jackson and Dave Watson netted Everton's other goals in the second half.
Tottenham moved up to sixth with their fourth win of the season over Manchester City. Once again Nayim, the hat-trick hero of the recent FA Cup quarter-final at Maine Road, was the decisive influence, scoring Tottenham's second goal. Their other marksmen were Darren Anderton and Andy Turner; Mike Sheron replied for City.
Chelsea recovered from the 18th- minute sending-off of their Republic of Ireland striker Tony Cascarino to draw 1-1 at Leeds. Cascarino was dismissed for elbowing David Wetherall, who later put Leeds ahead, but Chelsea levelled in the second half through a Mal Donaghy header. Leeds's Tony Dorigo, the only left- back in England's squad for next Wednesday's World Cup qualifying game in Turkey, limped off with an ankle injury just before the interval.
Millwall and Swindon consolidated their First Division promotion challenges, but Derby's play-off hopes receded after Shaun Cunnington eased Sunderland's relegation fears with a late winner at Roker Park.
Jamie Moralee gave Millwall a 1-0 home success over Luton with his first goal in nine games while Swindon beat Bristol City 2-1, their sixth successive home win. Swindon scored through the on-loan Brian Marwood and a Paul Bodin penalty while City, who had defender Matt Bryant sent off, had the consolation of a late goal from Leroy Rosenior. City's neighbours Rovers beat Peterborough 3-1, but remain at the bottom and suffered an additional blow when their full- back Lee Maddison was taken to hospital with facial injuries.
West Ham's First Division promotion hopes were hit hard by the Football Association yesterday when they lost two influential players, midfielder Martin Allen and left-back Julian Dicks, to suspensions. Dicks misses two matches while Allen, who was also fined pounds 1,000, has been banned for four fixtures.
West Ham, no doubt thinking of reinforcements, are reported to have offered pounds 200,000 for Bury's Islington- born midfielder, Ronnie Mauge.
A 3-2 win over Preston, including two goals from Bob Taylor, keeps West Bromwich Albion in the Second Division promotion frame.
The Association of Premier League and Football League Referees and Linesmen, has issued a 14-page document calling for change. They want assessments to be made by an independent panel, and not by club managers, and point out that their fees are among the lowest in Europe. They receive pounds 165 for a Premier League game, and pounds 130 for a Football League game.
The Netherlands beat San Marino 6-0 in Utrecht last night to move two points above England in World Cup Group Two; Norway are the leaders. Italy moved a point clear in Group One, which includes Scotland, with a 6-1 success over Malta in Palermo. Czechoslovakia, who are in Group Three along with Wales, were held 1-1 by Cyprus in Limassol.Reuse content