Kent's hopes of pipping Essex to the one promotion place in Specsavers County Championship Division 2 were all but ended when they subsided to a 10-wicket defeat to Northamptonshire at Beckenham.

Needing a fourth successive win to maintain pressure on the long-time leaders, Kent subsided inside three days to a Northamptonshire side still buoyed from winning last month’s NatWest T20 Blast title.

From the moment visiting skipper Alex Wakely went down the route of an uncontested toss to bowl first on a humid and overcast opening day, Kent were outgunned with both bat and ball with Northamptonshire fully deserving of their 23-point win.

Kent banked only four points, effectively downgrading their final match of the season, at home to Essex later in the month, to a dead rubber. Essex need just five points from their remaining two matches to secure the title.

Resuming on their parlous overnight score of 15-4 and needing 154 simply to make Northamptonshire bat again, Kent got off to a shaky start and had lost their skipper Sam Northeast (1) within half-an-hour.

Sam Billings, who only arrived in Kent at 3am after driving from Manchester overnight having been 12th man for England’s T20I against Pakistan, came to the crease to partner nightwatchman Hardus Viljoen.

The tall South Africa strike bowler soon showed his abilities with the bat by hooking Sanderson for four on his way to a classy 97-ball 50 with five fours.

He and Billings added 84 inside 20 overs for the sixth wicket before Viljoen, on 63 and nine short of his career-best, aimed to cut a wide one from Steven Crook only succeeded in edging to Ben Duckett at slip.

Then, in the lunch over, Billings (39), in trying to withdraw the bat against Crook chopped on to the base of off stump to trudge back to the pavilion with his side still 41 behind in the game.

Darren Stevens combined with Will Gidman to wipe out the arrears after lunch but Kleinveldt (5-53) removed Gidman, who sparred at a lifter to be caught behind at the second attempt by David Murphy.

Kent’s No.10 Matt Coles was lured into an expansive drive by spinner Rob Keogh only to toe-end the ball onto leg stump then, with his score on 44, Stevens aimed to clear the leg-side ropes against Keogh only to pick out Wakely at deep backward square leg.

Northamptonshire duly knocked off the 31 runs required to secure their third win of the summer with four sessions of the game in hand.

Fittingly it was Ben Duckett, the batsman who had played the match-defining innings with a double hundred on day two, who hit the winning run with a leg-side single soon after 3pm.

Opener Sean Dickson (63) had top scored in Kent 's first innings total of 230 while there were half-centuries for Gidman (51) and Coles (52) who added 55 for the eighth wicket. Gidman's fifty was his fourth in successive championship innings.

Northants got to stumps on 31 without loss and went onto dominate the second day led by 21-year-old opener Duckett, whose sublime 208 was his county's highest individual score against Kent, beating Jock Livingstone’s 200, scored at Maidstone in 1954.

It was the Farnborough-born player's fourth century of the summer, his second double this campaign, and was peppered with 26 boundaries.

He and skipper Alex Wakely (73) laid the platform for the Northants' total of 384, adding 171 in 37 overs for the second wicket though Wakely did enjoy a life on 27 when Stevens downed a sharp, overhead chance at short mid-on off the bowling off Gidman.

Duckett's five-and-three-quarter hour stay finally ended when he was caught at slip by Tredwell off Coles (2-79) and his departure sparked something of a collapse as the visitors lost their last six wickets for 37 runs to the second new ball. Viljoen finished with 3-91 from 24 overs while Mitch Claydon took 3-73 from 16.

Starting their second innings 154 runs adrift on the second evening Kent were soon in disarray losing Daniel Bell-Drummond (0), Dickson (3), Joe Denly - whose duck completed an unwelcome pair - and nightwatchman Tredwell (1) to reach stumps at 15-4.