Gough, who took three wickets on Saturday, claimed four more in just 21 balls at a cost of 12 runs. His previous best figures were 7 for 42 in the championship game against Somerset at Taunton two years ago.
Lancashire resumed on 70 for 3, facing a hopeless task, and Gough's burst, which brought him the wickets of Steve Titchard, Mike Watkinson, Ian Austin and Peter Martin, looked likely to end the contest well before lunch.
But the visitors mounted spirited resistance in the form of the wicketkeeper, Warren Hegg, and Gary Yates, who put on 93 in 16 overs for the ninth wicket after Gough retired from the attack.
Hegg struck some powerful blows to reach a fine half-century from 45 balls which included nine boundaries and had brave support from Yates, who finished unbeaten on 42. The stand was broken just before lunch when Hegg was bowled by Peter Hartley for a battling 64 from 56 balls with 11 fours.
The end came two balls into the afternoon session when Gary Keedy was caught in the covers by David Byas to give Hartley his third wicket.
Opener Richard Montgomerie keeps his place at the expense of out-of-form Mal Loye in Northamptonshire's side to face Worcestershire in today's Benson and Hedges Cup match at Northampton. Montgomerie, left out for the opening group match at Derby, hit a career-best 192 in Northamptonshire's victory over Kent.
Kent will be without their first-choice pace attack of Martin McCague and Alan Igglesden against Somerset at Canterbury today. McCague is suffering from a side strain while Igglesden is troubled by neck and back problems. The left-arm seamer, Tim Wren, and Julian Thompson, are called up.
Paul Smith, who won the gold award in last year's final, is in Warwickshire's squad for the first time this season as the holders take on Lancashire at Edgbaston. Smith is competing with Graeme Welch for an all-rounder's place.Reuse content