Yorkshire 428 and 101 for 5 (Duke 17*, Barker 3-22) leadHampshire 225 for 4 (Dawson 61*, Gubbins 58, Brown 52*) by 119 runs
Keith Barker gave Hampshire hope of beating Yorkshire at home in the LV= Insurance County Championship for the first time since 2008 with a wicked evening spell of fast bowling.
Lancashire-born Barker picked up three for 22 - with Kyle Abbott and Brad Wheal also picking up a wicket a piece - to ignite a match seemingly heading for a draw. Yorkshire slumped to 101 for five, a lead of 119 at the close.
Earlier, Hampshire's last four wickets put on 142 runs, which included a useful 38 from Barker, to frustrate the visitors before they were bowled out for 410. That meant Yorkshire took a slender 18-run first-innings lead, with the teams who started the round in second and third in Division One both picking up six bonus points each.
In a juxtaposition of county team-mate Jonny Bairstow's heroics in the Test match, things appeared to be meandering as Adam Lyth and first-innings centurion George Hill scored 36 in 18 overs. But wickets began to tumble, and trouble followed.
Barker picked up Hill pushing to James Vince at a wide first slip and Lyth nicking a classic delivery on a fourth stump line behind. The left-armer then bowled Harry Brook, via a deflection, for 10. It was the first time Brook had been dismissed for a score lower than 41 this season.
Will Fraine continued the collapse when Abbott found a patch of exaggerated bounce just back of a length to clip the shoulder of the bat through to keeper Brown.
Wheal joined in the carnage when Matthew Waite clipped uppishly to James Fuller at square leg to leave Yorkshire 81 for five before a short rearguard before stumps.
At the start of the day, Yorkshire needed to pick up the final six wickets before Hampshire passed the follow-on target, giving hope of repeating 2019's innings victory here. A new ball 11 overs into the day gave hope of that possibility.
Ben Brown and Liam Dawson, who both recorded half-centuries the previous evening, had their 118-run stand ended before the new ball appeared. Dawson was caught at first slip when attempting to drive spinner Dom Bess.
Yorkshire's fielding let them down at various points during the Hampshire first innings. Nick Gubbins had survived a drop and Brown a missed stumping on day two, and that trend continued into day three.
Harry Duke fumbled another stumping chance when Brown was on 53 before failing to break the stumps when Brown looked short of his ground. Aneurin Donald was also given two lives by Dominic Drakes and Lyth, which Yorkshire would later rue as they fell a wicket short of a seventh bonus point.
Brown departed seven overs into the second new ball when he pushed to first slip. Donald and Barker put on 57 before both fell within three overs; the former lbw to Matthew Revis and the latter bowled while missing a reverse sweep.
Fuller and Abbott put on the afterburners to race past 350, the South African flicking the most nonchalant of sixes over mid-wicket before his partner thrice stuck Bess over the ropes. Their 50 partnership came up in just 45 deliveries and eventually reached 74.
Jordan Thompson picked up the final two wickets in consecutive overs - Fuller and Abbott both holing out to the short legside boundary - to end up with four for 68.