The quartet will depart when their contracts expire on April 30, opening up plenty of room for coach John Aloisi to recruit in the off-season.

Dutch midfielder Marcel Meeuwis, defender Jamie Coyne and midfielder Cameron Edwards – all signed during the season – have also been released.

In good news for the Heart, Mate Dugandzic, Jonatan Germano, Nick Kalmar and Sam Mitchinson have agreed to contract extensions.

They have also signed Adelaide United winger Iain Ramsay.

Aloisi paid tribute to foundation players Colosimo, Thompson and Bolton and thanked Fred for his contribution as captain for the past two seasons.

"I was a foundation player of the club and I know first-hand how hard Simon, Matt and Clint worked to bring the club to life with their performances and their work off the field," Aloisi said.

"Fred has also been a great captain for the past two seasons and pushed himself to the limit every training session and every match.

"I know I speak on behalf of all the club's staff and members that we will always be thankful for their contribution."

Like the Heart, Colosimo, 34, endured a frustrating campaign, while Fred, 33, has been regularly sidelined by injury and Thompson, 30, is probably the unlikeliest of the four to miss out on a contract.

Bolton, 37, lost his starting spot in goals to Andrew Redmayne during the campaign.

The Heart want Bolton to remain in a non-playing capacity, while they are also looking to re-sign Richard Garcia and Jason Hoffman with contract talks ongoing.