Warwickshire director of cricket Dougie Brown has left Edgbaston after 27 years' service to the club, as both player and coach.
But they only avoided relegation in their final County Championship game.
Brown's departure by 'mutual consent' after four seasons in the job ends an association going back to when he first joined the playing staff, making his debut as a Second XI player in July 1989.
His job has not been made easy over the past two years by the dressing-room complications brought on by the enforced early retirement of captain Jim Troughton in 2014 and the decline of Ian Bell's England career.
"The club has a very proud history of challenging for silverware and, despite winning the One-Day Cup this season, failure to qualify for the T20 Blast quarter finals and narrowly avoiding relegation from Division One of the County Championship on the last day of the season is not where the club should be," said Brown, in a statement.
"It is, therefore, the right time for me to agree to step down from my role as Director of Cricket.
Bears chief executive Neil Snowball added: "Dougie is a true Bear, having served the club with great distinction as a player, coach and director of cricket."
Former Warwickshire boss Ashley Giles is among the list of candidates to succeed Brown, according to the BBC's Pat Murphy.
Giles has been in charge of Lancashire for the last two years, but still lives in the Midlands.
Another possibility is ex-England team director Andy Flower, who lives in Stratford and works in a high-ranking coaching capacity for the ECB at Loughborough.
But no announcement is expected soon and the process of finding a successor could roll into November, as historical precedent suggests that Warwickshire will not rush into any new appointment.
When Giles left in November 2012, it was a month and a half before Brown was appointed.
by BBC WM's Richard Wilford
"Dougie Brown has been at the heart of Warwickshire cricket for three decades as a player, coach and director of cricket.
"He is one of the last links to the Bob Woolmer/Dermot Reeve era at Edgbaston, and has consistently set high standards for himself and the county, filling the trophy cabinet along the way.
"The summer was a difficult one for Brown's Bears despite their Royal London One-Day Cup triumph at Lord's last month.
"Their form in the County Championship was sketchy at best. Nonetheless, this is not a decision either Warwickshire or Dougie will have taken lightly."
Dougie Brown's time with the Bears
•Having first represented Warwickshire's second XI in July 1989, Brown made his first-class debut in April 1992.
•He played 197 first-class matches in his 15 years with the Bears, making 8,066 runs at 30.50, as well as taking 515 wickets.
•Brown also hit 4,096 runs in 263 one-day matches, taking 309 wickets.
•Dual international, having represented both England (9 caps) and Scotland (30 caps). He also coached Namibia at the 2003 World Cup.