Joe Root took three of four wickets to fall as Yorkshire secured a crucial Roses win over Lancashire by 118 runs during the third morning at Emirates Old Trafford.
The White Rose’s third Specsavers County Championship victory in eight matches also deepened their arch-rivals’ relegation worries given they have only secured one win from their first nine outings, losing five.
Steve Patterson’s side were defending a target of 323 and started day three on the verge of a 19-point haul.
Lancashire, who claimed only two points having been deducted one for a slow over-rate, were 194-6 with only Tom Bailey, unbeaten on 38, Graham Onions, Jimmy Anderson, Matthew Parkinson and the injured Liam Livingstone to bat as they pursued another 129 to win.
Home captain Livingstone had fractured his left thumb while fielding on day one and did not bat in the first innings.
However, he came out at number 11 in the second without facing a ball as Lancashire lost their last four wickets for 10 runs in slipping to 204 all out.
He now faces a significant spell on the sidelines.
Root, having dismissed Jos Buttler in the penultimate over of day three, struck with the first ball of day three when Onions edged behind for a duck.
Then, shortly afterwards, he had Parkinson caught at first slip as the score fell to 196-8 in the 53rd.
Patterson trapped Bailey LBW for 45 before Root bowled Anderson on the way to career-best figures of 4-5.
Yorkshire started the match second-bottom in the table, three points behind Lancashire with a game in hand, but are now 14 points clear.
They have also jumped over Hampshire, who have not played this round and are in the relegation zone as a result.
Hampshire are one point behind Lancashire with a game in hand and 15 points behind Yorkshire with both counties having played eight matches.
Lancashire have not won a Roses Championship match since completing the double in 2011.
Attentions now return to the Vitality Blast, with Lancashire leading the North Group with five wins from six.
Their next Championship outing comes on August 19 when they travel to the Oval to face leaders Surrey in a pink ball fixture.
The Red Rose only have one more home match in their remaining five against Worcestershire at Southport as the Old Trafford outfield gets relayed.
Meanwhile, prior to the start of play, Lancashire awarded first-team caps to Jos Buttler, Keaton Jennings and Dane Vilas.