Dom Bess finished with 6-53 as Yorkshire wrapped up a fabulous comeback victory over Sussex, by 48 runs, shortly after midday on day four at Hove.
Set 235 to win, Sussex started the final day on 136-5 from 52 overs and had advanced to 180-7 in the 68th through captain Ben Brown’s 46.
But Test captain Joe Root took the first of three wickets in as many overs with his off-spin as the visitors fell to 186 all out in the 70th, with Jordan Thompson and Bess also striking.
England off-spinner Bess had claimed five wickets on day three as he bowled through a cartilage injury just below his rib.
And he wrapped up the 19-point triumph by getting Henry Crocombe caught above his head by David Willey at mid-wicket.
While Bess will take the headlines for this performance after a challenging winter away with the national team, Willey was also a key contributor in helping the White Rose leapfrog Sussex to go top of the Group Three table at time of victory.
After Yorkshire were bowled out for 150 in the first innings, they conceded a 71-run lead.
At the end of Yorkshire’s second innings, Willey and Duanne Olivier shared a 10th-wicket partnership of 51. In the end, that proved the difference between defeat and a second away win in as many weeks.
Steve Patterson made the initial breakthrough during the seventh over of the day when he trapped Ollie Robinson lbw for six.
After two previous lbw shouts from skipper Patterson had been turned down, Sussex fell to 145-7 in the 59th over, still needing 90 more to win.
Jack Carson then edged Patterson wide of the slips for four on a couple of occasions, while Brown advanced from 26 not out overnight to 46, with Sussex 180-7 after 67 overs and nerves jangling in both dressing rooms.
But Patterson introduced Root into the attack in place of Bess from the Sea End of this ground, and he struck with only his third ball to get Carson caught at slip by Adam Lyth.
That left Sussex eight down needing 55 more.
And five balls later, Thompson put Yorkshire on the verge when he uprooted Brown’s middle stump as the Sussex skipper half-heartedly attempted to give himself some room by stepping towards leg.
Sussex were 180-9 in the 69th over.
Root only bowled the one over, and Bess, who had started the morning with ball in hand and bowled 29.5 overs in all, returned to put the cap on things with Willey’s help.
After a home draw against Glamorgan and away wins here and at Kent last week, Yorkshire have 53 points.
They were awaiting Lancashire’s result at Kent to see whether they would remain top of the table at the end of the round.
Yorkshire are back in action against Northamptonshire at Emerald Headingley, starting on Thursday.
The plan is for Root to rest as he prepares for England’s summer schedule, which begins in early June. He will return to Yorkshire colours before then, but it is not yet clear exactly when.