Leicestershire 304 and 96 for 6 (Sanderson 5-51) lead Northamptonshire 191 (van Beek 4-47) by 209 runs
Leicestershire will take a lead of 209 into day three of their Rothesay County Championship match with neighbours Northamptonshire after 16 wickets fell on a dramatic second day.
The Division Two leaders bowled out Northamptonshire for 191 to lead by 113 on first innings, after
Logan van Beek had taken 4 for 47 and Ben Green an excellent 3 for 17 in an impressive display of seam bowling. Allrounder Justin Broad's 36 represented a modest top score for the visitors, who at one point were 87 for 6.
Northamptonshire's
Ben Sanderson then single-handedly reduced Leicestershire to 52 for 5 in their second innings before they closed on 96 for 6.
The day's drama began in the second half of the morning as Northamptonshire's response to Leicestershire's first-innings efforts unravelled at pace, five wickets falling for 14 runs in the 30 minutes before lunch.
Until then, batting had looked less hazardous than on Friday as the first 21 overs of the day rewarded the home attack with only the wicket of Luke Procter, trapped on the crease by Josh Hull.
But then, with a relatively sunny start giving way to cloud, 73 for 1 became 87 for 6 in the space of 41 balls with the bowlers again finding movement through the air and off the pitch.
Green, the seamer from Somerset in his fourth loan spell in two seasons at Grace Road, began the collapse via a catch behind the stumps as a swinging, bouncing delivery glanced off the bat of Ricardo Vasconcelos as he tried to leave.
Tom Scriven dismissed George Bartlett leg before in the next over before Green's movement deceived James Sales, who was bowled shouldering arms. Netherlands international van Beek then took two wickets in two overs immediately before lunch, pinning Rob Keogh and then Lewis McManus leg before.
Northamptonshire were thus in disarray at 87 for 6 at the break, after which 191 all out at tea was better than they might have feared, Broad showing some fight to make what might be valuable runs before a good ball from Scriven found the edge.
Sanderson and Harry Conway then frustrated Leicestershire by adding a plucky 34 for the last wicket before Sanderson was caught at first slip for 18. He had two escapes - on nought, when Rehan Ahmed wasted a run-out chance by missing the stumps from two yards, and 1, when he was dropped at first slip.
Green was the culpable fielder, although he more than made amends with a masterclass in seam bowling, picking up his third wicket when extra bounce had Calvin Harrison caught at third slip. Green conceded only one boundary, bowling 71 dot balls from 84 deliveries in total.
Van Beek, who had earlier had Saif Zaib caught at third slip with a superb delivery, dismissed Sanderson to raise his tally for the season to 14.
Northamptonshire's 10 wickets had fallen in the space of less than 50 overs but there were no immediate signs of conditions becoming easier as Sanderson then proceeded to rip through Leicestershire's second innings, their lead suddenly looking slim as they floundered at 52 for 5.
Rishi Patel, compiler of a brilliant first-innings hundred, was tamely caught behind on the leg side without scoring, while Budinger, after a typically explosive 39 from 24 deliveries - including five fours and a six off Sanderson - followed four consecutive boundaries by chopping on to his stumps.
Sanderson then had Lewis Hill edging to third slip and Rehan to second, either side of a second-ball duck for skipper Peter Handscomb, trapped squarely in front. Sanderson's last four wickets had come in 10 deliveries, the only runs conceded for a no-ball.
The second of Sanderson's five took him to the milestone of 400 wickets in first-class matches for Northamptonshire, having earlier passed 1000 first-class runs for the county.
Ben Cox was sixth out at 75, gloving Conway down the leg side, before van Beek and Ian Holland, the latter hit on the helmet by Procter, survived a tough 12 overs to the close.