Treble-winning midfielder Max Balard is the latest player to leave Central Coast, joining Dutch top-flight club NAC Breda.
The 23-year-old was contracted for one more A-League Men season but has been granted a free transfer under the terms of that deal.
Breda, one of current Socceroos and former Mariners coach Graham Arnold's clubs during his playing days, were promoted to the Eredivisie via the play-offs last season after five years in the Dutch second tier.
Balard was part of back-to-back championships with the Mariners and played a key role in this year's historic treble.
It included the AFC Cup as well as the ALM premiership and championship - the latter decided with an extra-time win over Melbourne Victory in the grand final.
Balard missed just one of 44 matches throughout the campaign and was named the Mariners Medallist.
"We would like to thank Max for his dedication during his time at the Mariners," Central Coast coach Mark Jackson said.
"He was a great player to work with, someone who was really hungry to learn and get better every day.
"It is great to see Max get his opportunity overseas.
"We knew that was what he wanted, and we wish him well and thank him for his contributions.
"He was exceptional last season, helping us win the trophies that we did."
Balard's exit follows that of fellow treble winners Ronald Barcellos and Jing Reec, who departed when their respective loan deals ended.
Former club captain Danny Vukovic has retired, while defender Dan Hall has joined ALM newcomers Auckland FC.
The 25-year-old won four titles with the Mariners and made 91 appearances for the club.
"There were quite a few clubs vying for Dan's signature," Auckland coach Steve Corica said.
"He's an outstanding player, but he really bought into what we're aiming to achieve here and the future pathways the club can offer thanks to (club owner) Bill Foley's multi-club network.
"He's going to slot right into that defence.
"He's got a lot of experience and won a few trophies, so will likely act as a bit of a leader for some of the other lads at the club."
Elsewhere, Brisbane Roar midfielder Henry Hore has re-signed with the club and joined K League 1 team Gangwon FC on a six-month loan with the inclusion of an undisclosed loan fee.
The 24-year-old will return to Brisbane at the start of January.
"I'm super excited. It's a very good league," Hore said of the South Korean top flight.
"I'm very thankful to the Brisbane Roar management for allowing me to go and pursue this opportunity and I can't wait to get started."
Olyroos midfielder Keegan Jelacic will remain with Brisbane next season after signing a 12-month loan extension from Belgian Pro League side KAA Gent.