Durham's record wicket-taker Graham Onions leaves club 'with heavy heart'
The 35-year-old had hoped to be offered a two-year deal and the chance of a coaching role at the county, but the two parties couldn't agree terms.
It means the former England man will play his cricket elsewhere next season, following Paul Coughlin out the door.
A statement from Durham CCC said: "The club and player have been involved in long discussions in recent weeks and were able to agree financial terms.
"However, Graham and the club could not reach agreement on the offer of a two-year extension where the second year is conditional on Graham avoiding serious injury in year one. And although the club are keen to support Graham in pursuing a coaching career beyond his playing days, there could be no guarantee of an appointment to the professional coaching team on his retirement.
"At such an important point in his career DCCC understand Graham’s desire to maximise his security.
"Graham has played a huge part in the history of Durham County Cricket Club since making his first-class debut in 2004. He was part of the County Championship winning side in both 2008, 2009 and 2013 and helped Durham win the Royal London One Day Cup in 2014.
"DCCC are extremely proud of Graham’s development that saw him play Test cricket for England and recently become Durham’s leading first-class wicket-taker.
"The club would like to thank Graham for his exceptional service and wish him well for the future."
Onions became Durham's record wicket-taker earlier this month when he bagged his 519th dismissal against Kent.
He played nine Tests for England, taking 5-38 on his debut against West Indies at Lord's.
He has been hit by injury the last couple of seasons, however, and has played just seven first XI games this year after having back problems, taking 27 wickets in Division Two.
Onions said: “It has been the hardest decision I have ever had to make. I genuinely love Durham County Cricket Club and hoped to finish my career here.
“Unfortunately, we were unable to agree on the length of contract and there doesn't appear to be any guaranteed opportunities for a coaching role in the future.
“So, with a heavy heart I have to leave Durham to ensure a securer future for my family. I would like to thank the club and the members for your support over the last 15 years.
“I hope I will be remembered for wearing the Durham badge with pride and always giving 100%. Durham will always hold a special place in my heart and I hope to return one day."