Northants 165 for 8 (Levi 41, Keogh 37, Pillans 3-33) beat Leicestershire 107 for 3 (Cosgrove 41) by two runs (D/L method)
Northamptonshire ended Leicestershire's 100 per cent record in this year's NatWest T20 Blast with a two-run Duckworth/Lewis win at Grace Road.
The Foxes, batting second, had only themselves to blame, having been ahead of the D/L calculation for much of their reply after the Steelbacks had scored 165 for 8 on a hard and true pitch.
Northants were indebted to a partnership of 75 between captain Alex Wakely and Rob Keogh, who came together after Richard Levi was well caught low down at deep square-leg by Dieter Klein off Gavin Griffiths for 41, leaving the score at 68 for 4 in the 10th over.
But Wakely and Keogh kept the scoreboard moving, the former hitting consecutive boundaries off Klein before 21 came from the 17th over, bowled by Mat Pillans.
Both bowlers came back strongly, Pillans knocking back Wakely's leg stump as he stepped to the offside and tried to lift the ball over short fine-leg, and then Klein picking up the wickets of Steven Crook and Rory Kleinveldt with consecutive deliveries to restrict the Foxes' target to under 170.
They were given a good start by Luke Ronchi and Cameron Delport, who added 45 for the first wicket before the New Zealander steered Ben Sanderson to backward point, where Ben Duckett took a smart two-handed catch.
Off-spinner Keogh bowled Delport for 30, but Mark Cosgrove, who was particularly severe on left-arm spinner Tabraiz Shamsi, hit 41 off just 26 balls to leave the Foxes in control.
Leicestershire were still ahead on D/L when the Australian was bowled swinging across the line at Kleinveldt.
But neither Colin Ackermann and Mark Pettini were able to get the ball to the boundary before umpires Steve O'Shaughnessy and Ian Blackwell took the players from the field, with the home team having fallen fractionally behind the required rate.