A rapid half-century by Steven Crook gave Northamptonshire the platform to open their Yorkshire Bank 40 account for the season with a 42-run win against Worcestershire at New Road.
The home side only had themselves to blame as they spilled four chances - including one from Crook when he had made 10 - and the allrounder made them pay by charging to an unbeaten 61 from 42 balls.
Crook's blitz, bringing seven fours and two sixes over the longest boundary at midwicket, helped the Steelbacks to a match-winning total of 219 for 6 after adding 61 from the last five overs. This gave Worcestershire too much to do on a tricky pitch and they were dismissed in the 38th over for 177 despite Thilan Samaraweera's masterclass in one-day batting.
Samaraweera caressed the ball around the field, hitting nine fours in making 78 from 81 balls, but the chase was over when he became the first of two lbw dismissals in successive deliveries from Andrew Hall. Northamptonshire's fielding was top notch throughout and they delivered the most decisive spells with the ball.
David Willey broke through at the top order and Matthew Spriegel took wickets in successive overs before finishing with 3 for 29. Samaraweera gave his side hope in stands of 53 with Daryl Mitchell (29) and 58 with Gareth Andrew (21), but it was never easy to get the ball away on a sluggish surface.
Andrew was the big threat to Northamptonshire at that stage but, after driving one six off Crook, the left hander was well caught by Kyle Coetzer as he speared a shot from Trent Copeland low to point.
In difficult conditions for the big hitters, Crook was the exception in having the power to hit through the line in making his second List A fifty for the county.
Earlier, the Northamptonshire openers kept things ticking over in a partnership of 62 before Brett D'Oliveira had a hand in their dismissals, taking a simple catch from David Sales at mid-on and bowling Rob Newton as the batsman attempted to cut.
Alex Wakely played well for 35 before falling to Jack Shantry, and offspinner Moeen Ali produced the ball of the day, turning and clipping the top of Spriegel's off stump. However, Moeen's last over, costing 18 runs, was crucial for Northamptonshire as it brought sixes for Willey and Crook.