Preston blew the chance to put daylight between themselves and the npower Championship drop zone after drawing 1-1 at third-bottom Bristol City.
Iain Hume had given North End a second-minute lead but Billy Jones put through his own net 19 minutes from time.
Coventry missed an opportunity to go third as Leeds won 3-2 at the Ricoh Arena.
Jonathan Howson and Robert Snodgrass put United 2-0 up before half-time. Lukas Jutkiewicz pulled one back but Max Gradel's penalty gave Leeds breathing space before Ben Turner set up an anxious finish.
Norwich also had a chance to go third but will be pleased with a point after coming from two goals down to draw 2-2 with Burnley thanks to Andrew Crofts' stoppage-time equaliser.
However, Crofts' afternoon ended on a sour note after he was sent off moments after scoring.
Martin Paterson's double saw the Clarets lead 2-0 until the 71st minute, when Russell Martin pulled a goal back.
Hull remain in danger towards the bottom of the table after Michael O'Connor scored a minute from time to give Scunthorpe a 1-0 win at the KC Stadium. ut Leicester eased their own relegation fears with a 2-0 success at Barnsley, Angelo Miguel Vitor and Andy King with the goals.
Doncaster came from behind to beat Millwall 2-1, James Hayter and David Healy netting in two second-half minutes to cancel out Steve Morison's opener.
Watford and Nottingham Forest played out a 1-1 draw at Vicarage Road, Lewis McGugan levelling after Jordon Mutch had given the home side a third-minute lead.
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