COUNTY CHAMPIONSHIP DIVISION ONE, Headingley:
Kent 302 & 90-6 beat Yorkshire 261 & 130 by four wickets
Kent 22 pts, Yorkshire 5 pts
Gerard Brophy is stumped first ball to become the second victim of Tredwell's hat-trick
James Tredwell took 7-22 to end Yorkshire's hopes of winning the County Championship, but could not stop Kent from being relegated from Division One.
The England off-spinner also bagged a hat-trick as the Tykes collapsed from 93-1 to 130 all out.
Kent wobbled chasing their target of 90, but eventually got home six down.
Yorkshire needed a victory to have any hope of taking the title, while Kent's slim hopes of survival were ended by Warwickshire's win against Hampshire.
There was no sign of the trouble to come for Yorkshire when Adam Lyth and Anthony McGrath added 42 runs in the morning session to take their second-wicket stand to 53.
But when McGrath was caught behind off a spitting delivery from seamer Dewald Nel (3-57), it began a collapse that saw the Tykes lose their last nine wickets for 37 runs.
Captain Andrew Gale was bowled by Nel, Lyth fell in the same fashion to Tredwell and, from the next ball, Gerard Brophy was lured out of his crease and stumped by Geraint Jones.
From the first ball of his next over Tredwell persuaded Jonny Bairstow to lob a catch to midwicket and from there, save two sixes from Ajmal Shahzad, the Yorkshire tail folded.
Kent openers Joe Denly and Sam Northeast were trapped lbw by Moin Ahraf and Shahzad respectively, but the visitors looked to be cruising to victory in the shape of a third-wicket stand of 60 between Martin van Jaarsveld (44) and Robert Key (27).
But when Key was removed by Steven Patterson, Kent lost four wickets for 14 runs before they were dragged over the line by Tredwell's pull for four.
Yorkshire's consolation comes in the shape of £100,000 prize money, while Kent return to Division Two after a solitary season in the top flight.