David Sales made the first half-century of the match as Northamptonshire went into the final day of their clash against Hampshire in control.
Hampshire were skittled before tea for 154, 64 runs behind the hosts' first-innings total of 218, with James Vince making an unbeaten 46 off 74 balls and Northants captain Andrew Hall taking for for 24.
Northants then extended their lead to 240 as they closed on 176 for five, with Sales making 58 off 96 deliveries, including seven fours, and David Balcombe the pick of the visitors' bowling, taking two for 63.
Hampshire began the day on 42 for three, 176 runs behind their opponents, with their stand-in captain and Australia international Simon Katich on four and Liam Dawson on 14.
Dawson was to move on to 35 before he missed his attempted drive off David Willey in the 11th over of the day and his leg stump was sent tumbling.
Hall brought himself on and took two wickets in three balls in the 33rd over as first Lee Daggett took a good low catch in front of him at short midwicket to dismiss Katich (13).
History repeated itself two balls later as the same combination did for former Zimbabwe international Sean Ervine who needlessly chipped to Daggett, again standing at short midwicket.
Hampshire wicketkeeper Michael Bates was next to depart, for a nine-ball duck, when he edged Daggett to Stephen Peters at third slip to leave to visitors floundering on 84 for seven.
The eighth-wicket pair of Vince and Chris Wood added 58 between them either side of lunch before Wood was trapped lbw by Willey for 26.
Balcombe (two) soon followed when his off stump was taken out by Jack Brooks before Willey bowled David Griffiths for a duck to end the Hampshire innings.
Rob Newton went cheaply for 14 in the eighth over of Northants' second innings when he edged Balcombe to give Dawson the easiest of catches at second slip.
Peters then fell on 22 when he was pinned lbw by Ervine and Kyle Coetzer followed in the third over after tea for 25 when he was taken by Dawson at second slip off Balcombe.
Dawson took his sixth catch of the match when he snared Alex Wakely (15) at second slip off the bowling of Wood.
Sales completed his half-century off 90 balls before he eventually perished late in the day when he was caught leg before to give Dawson his first wicket.
