|LV County Championship Division Two, Chesterfield|
|Close of play, day two: Northants 267 & 285-6, Derbyshire 190|
|Derbyshire 3pts, Northants 3pts|
Chaminda Vaas bagged his sixth five-wicket haul of the season to bowl out Derbyshire for 190, earning Division Two leaders Northants a lead of 77.
Alex Wakely (83) and David Sales (65) then made half-centuries as Northants ended day two on 285-6, 362 in front.
The match was in the balance at the start of the day as Derbyshire resumed 151 behind with six wickets intact.
But Northants struck three times in the first seven overs to seize the initiative, Vaas finishing with 5-65.
That took the former Sri Lankan Test bowler's Championship tally this season to 57.
Derbyshire then hit back before lunch when Niall O'Brien was lbw playing across the line at Tim Groenewald.
The home side needed a big afternoon session to get back in the game and Mark Footitt raised their hopes by striking twice in successive overs, to have Kyle Coetzer taken low at second slip and Stephen Peters caught behind for 32.
When Rob Newton slapped Clare to cover, Northants were 91 for four, still only 168 ahead, but Wakely (83) and Sales (65) turned the game with a century stand.