Durham went one point clear at the top of Division One after a 10-wicket victory against struggling Surrey.
Surrey resumed on 185-3 but once Usman Afzaal was dismissed for 73 to leave them 261-4, wickets started to tumble.
Liam Plunkett nipped out Chris Schofield and Matthew Spriegel before Steve Harmison (4-102) ripped out the tail as Surrey were dismissed for 323.
Mark Stoneman (60 not out) and Michael di Venuto (57 not out) saw Durham to the 134 target with 10.2 overs in hand.
Afzaal and partner Jon Batty strode out to bat at the start of play with Surrey still five runs short of making Durham bat again and the former was the more aggressive of the pair.
After bringing up his fifty in 74 balls he clubbed off-spinner Paul Wiseman over midwicket for six but 20 minutes before lunch Wiseman had his revenge when Afzaal was caught behind cutting, ending a stand of 135 in 37 overs.
Batty completed a patient 140-ball fifty but ran himself out first ball after lunch, Steve Harmison shattering the stumps with a direct hit from a tricky angle.
In the next over Chris Schofield completed a pair when he edged his first ball, from Plunkett, to wicketkeeper Phil Mustard.
Plunkett then removed Spriegel with the second new ball and Steve Harmison polished off the innings with a spell of 3-10 in 13 balls.
Jimmy Ormond and Murtaza Hussain were comprehensively bowled and last man Jade Dernbach edged to Ben Harmison at slip.
Openers Stoneman and Di Venuto removed any anxiety Durham may have had by taking 40 off seven overs before tea and they ushered their side to victory with just over 10 overs left in the match.
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