Northamptonshire 442 and 214 for 6 (Keogh 74) lead Lancashire 315 (Davies 147, Croft 78, Sanderson 4-62) by 341 runs
Rob Keogh ensured Northamptonshire will enter the final day against Lancashire with a chance to press for victory at Wantage Road. Keogh made 74 from a tricky position to help Northants close day three on 210 for 6 in their second innings with a lead of 341.
Keogh's half-century, just his second of the season, was a vital innings after Northants slumped to 14 for 3 as they looked to build on a first-innings lead of 127. But Keogh, after a typically jittery start, settled well to flick and drive with good purpose.
He struck seven boundaries in passing fifty in 97 balls and was helping his side make serene progress after tea before being run out, called through for a single by Adam Rossington that Keogh was hesitant to accept after nudging Stephen Parry to the right of short-midwicket. Haseeb Hameed dived to his right to field, throw at the non-striker's end and Parry had the bails off before Keogh's dive arrived.
The dismissal stalled Northants, who with Keogh and Rossington had added 54 in 8.3 overs. Rossington was intent on scoring quickly and pulled Richard Gleeson over deep square for six in reaching 33 from 30 balls before losing his off stump to a beauty from Parry that gripped past his outside edge.
Luke Procter and Brett Hutton made far more sedate progress to the close but swelled the lead with the help of a seven - Hutton's edge to third man for three followed four overthrows.
It left Northants pondering an overnight declaration - which would give them use of a second new ball if needed late on the final day.
Initially, Lancashire mounted a fightback after lunch taking three wickets at the start of the Northants second innings inside five overs. Graham Onions and Gleeson tore in with the new ball. Onions swung one into the left-handed Ricardo Vasconcelos and nipped one back to the right-handed Richard Levi to win to lbws before Temba Bavuma drove Gleeson to point.
Lancashire sensed a way back into the game but with Saqib Mahmood not taking the field, the change bowling posed a significantly less threat and Keogh set out making a smart recovery with Rob Newton, sharing a calming stand of 96 for the fourth wicket before Newton fell for 48 after tea, edging a cut at Gleeson to wicketkeeper Dane Vilas.
Aside from the wobble, it was a fine day for Northamptonshire who, after a frustrating first hour, dismantled the Lancashire lower order, taking 5 for 25 with the second new ball. Alex Davies and Steven Croft extended their fifth-wicket partnership to 135 and Davies went past his previous first-class best of 140 but, to the final ball of the 80th over, miscued a pull against Keogh's offspin and was held at short midwicket by Temba Bavuma for 147.
An end was opened and Northants sensed an opportunity with a new ball in their hands. Steven Croft quickly fell, pinned lbw on the back foot by Ben Sanderson for a season's best 78 before Hutton took the middle and off stumps of Parry out of the ground.
Hutton struck again, having Mahmood caught at first slip for just 1 before Sanderson nipped one back to take an inside edge from Onions who made just 4. Gleeson then drove Hutton to provide Rossington with a second catch of the morning to hand Northants a 127-run lead and control of the match.