Ben Coker has signed a new three-year contract with League One newcomers Southend United, with an option for a further 12 months.
The 26-year-old defender joined the Blues in the summer of 2013 after leaving Colchester, initially on trial.
Coker has since made 90 appearances for Southend in all competitions and helped them to promotion last season.
"I've had a great time here since I first came and I'm thrilled to be able to stay," he told the club website.
"I feel like my game has improved massively since I joined the club, we had a great season last year and I'm sure this campaign and in the future we'll earn more success."
Meanwhile, Graham Coughlan has stepped up from first-team coach to become boss Phil Brown's new assistant manager, signing a three-year deal.
Southend start the new season away at Fleetwood Town on Saturday.