Leicestershire 519 and 49 for 0 lead Northamptonshire397 for 7 (Newton 202*, Keogh 50) lead by 171 runs
Rob Newton's maiden first-class double century led Northamptonshire out of danger on the third day at Wantage Road.
Newton's unbeaten 202 carried Northants to 397 for 7 before they declared 122 behind to potentially help set up a final day run chase. Leicestershire closed on 49 without loss in their second innings, leading by 171.
Both sides need victory, Northants especially, to keep their promotion hopes alive and Alex Wakely's declaration has opened up the game.
Newton's rearguard double century dented Leicestershire's first route to victory by seeing Northants past the follow-on mark. He left well, defended solidly and nudged the bowling around where possible. Calm throughout, his only moment of fortune was a top-edged pull that fell just short of deep square running in after reaching his ninth first-class century from 208 balls.
Two healthy partnerships steered Northants away from trouble at 184 for 5 10 overs into the third day replying to the visitors' 519. Newton batted through the first half of the day with Saif Zaib, who made a composed 43 in a partnership of 81 in 35 overs.
The pair slowly began to move Northants towards safer waters but Zaib edged Neil Dexter, with the second new ball, to second slip and when Rory Kleinveldt was run-out coming back for a second by a direct hit from Rob Sayer, Leicestershire's hopes of enforcing the follow-on were raised.
A second stand was needed for Northants to avoid the prospect and Steven Crook, batting down the order after a calf injury and with a runner, added 101 for the eighth wicket with Newton who brought up his double hundred off 342 balls with a flick to fine leg.
Initially, Leicestershire held control of the game. Northants resumed 142 for 4, 377 behind, and removed Adam Rossington for 26 after a rather skittish innings. He began with a skip down the pitch to lift Rob Sayer over long-on for six and added four boundaries - a perfect straight drive, a short arm pull, a top-edged cut over gully and an outside edge wide of third slip. He never settled and, pushing hard at Clint McKay, was taken at second slip.