Derby County moved six points clear at the top of the English second division after beating Burnley 1-0 as rivals Birmingham City and Preston North End both slumped to defeats on Tuesday.

Derby, who had won their six previous games including Saturday's FA Cup fourth round tie with Bristol Rovers, added a seventh with an early goal by striker Steve Howard.

Burnley finished the game with 10 men after a last-minute red card for new loan signing Eric Djemba-Djemba.

Derby have 59 points, while Birmingham, beaten 3-1 by lowly Southend, and Preston, who lost 1-0 to Colchester, are both on 53.

Birmingham went in front after nine minutes through an own goal by Southend defender Peter Clarke.

But they were pegged back by Kevin Maher's 22nd minute equaliser against the run of play and were trailing to Freddy Eastwood's strike just three minutes after the restart. Mark Gower got a late third to put the result beyond doubt.