Kyle Coetzer smashed a brilliant unbeaten century as Northamptonshire thrashed Worcestershire by seven wickets to win their fifth Yorkshire Bank 40 game in a row.
The Royals' innings never got going as they were restricted to 187-8 from their 40 overs with 19-year-old Tom Fell top-scoring with 55 off 71 balls as Mohammad Azharullah took 4-37.
Unsurprisingly, the in-form Steelbacks chased down their target with 37 balls to spare with Coetzer hammering 105 not out from 110 deliveries to move the hosts up to second in Group A - three points behind Nottinghamshire.
The hosts won the toss and chose to bowl and they claimed the wicket of Moeen Ali (12) in the sixth over when he tamely chipped Andrew Hall to David Willey at mid-on. Willey then dismissed the Royals' captain Daryl Mitchell for 15 in the following over when his delivery went through the gate and on to the middle stump.
Alexei Kervezee fell for just four when he was bowled by Azharullah before Sri Lanka international Thilan Samaraweera was run out on 12 by Hall from cover. Gareth Andrew then went cheaply on 13 when he smashed Matthew Spriegel to Ben Duckett at deep square leg.
Fell was to complete the first half-century of his senior career off 63 balls but his innings came to an end when Azharullah's yorker crashed into his off stump. The Royals' wicketkeeper Ben Cox (two) was then bowled by Azharullah before teenager Aneesh Kapil chopped the same bowler onto his stumps to depart for 28.
Brett D'Oliveira and Jack Shantry survived the final 17 balls unbeaten on 19 and six respectively but Worcestershire's total looked well below par.
Chasing 188, Northamptonshire lost Willey for 13 in the fourth over when he was sharply caught and bowled by Shantry. Mitchell brought himself on in the 14th over and soon caught and bowled Australia international Cameron White, who made 24 in the first game of his second spell with the Steelbacks.
Coetzer then went on to reach 50 off 63 deliveries as his third-wicket partnership of 121 with home captain Alex Wakely took the game away from the visitors.
He completed his third century in domestic one-day cricket off 107 balls before Wakely holed out on 43 when he launched Kapil to Chris Russell at long on but Spriegel nudged the winning run with a single off Mitchell in the 34th over to complete a comfortable victory.