England batsman Keaton Jennings is the latest in a lengthening list of players to confirm he will leave Durham CCC at the end of the season.
Jennings turned down a contract extension to stay with the Division Two side long term and has instead signed for Lancashire.
As a result he will depart after this week's closing County Championship fixture with Worcestershire.
Coughlin penned a deal Nottinghamshire last week, who look set to seal promotion to the top flight this week.
A club statement explained the decision: "Following long discussions, Keaton has decided that at this critical point in his international career he needs to play first division cricket and we respect his decision.
"It has been a pleasure to see Keaton develop through the Durham system and to break into the England team."
Jennings admits that he leaves the county with a heavy heart.
"My heartfelt gratitude goes to Durham County for the opportunities, support and guidance in enabling me to follow my dream of playing cricket in England," he said.
"My years at the county have been positive and inspirational and I leave with the happiest of memories and the closest of friends.
"Despite being career-driven, the decision to move on has been agonisingly difficult for me.
"Everyone in the north has become, and will remain, family to me.
"I wish consolidation and success to DCCC."
Chairman Sir Ian Botham said, "Keaton has been an important player for Durham, a natural leader and I have been hugely impressed by his professionalism and courtesy through what has been a very difficult decision for him.
"I would like to take the opportunity to wish him well for the future."