Former footballer and Nine News Adelaide sports presenter Warren Tredrea has lost his unfair dismissal court case against his former employer.

Tredrea sued Channel 9 South Australia, claiming the network unfairly terminated his contract in January 2022 because he refused to get the COVID-19 vaccine.

The former Port Adelaide captain and premiership player was seeking almost $6 million in lost wages.

The Federal Court dismissed Tredrea's case and awarded costs to Channel 9.

Justice Geoffrey Kennett accepted Nine's counter-argument that Tredrea's contract was not going to be renewed in November 2022 because of his performance in the job.

Speaking outside his lawyer's chambers following the decision, Tredrea hinted he might appeal.

"Obviously, it's not what we were hoping for at this stage of the proceedings, it's disappointing," he said.

"We'll have to speak with my legal team to work out where we go from here, whether we consider an appeal.

Tredrea acknowledged the financial impact of the proceedings.

"It's been a significant outlay to take this on, but yeah, we're very adamant that we've gone the right course and wouldn't have gone this far if we didn't," he said.

"I want to thank all the people who have supported me, people who have stopped in the street, people who contact you on social media. It's been a challenging period, a difficult one, we didn't get the rub of the green today, but … might not be over."

Tredrea launched legal action in September 2022, and claimed that he should be paid out the remainder of his 2022 salary — $176,458.32. 

He also sought compensation for the loss of opportunity to renew his contract for up to 30 years, which equated to $5.775 million.

During the case, Channel 9 said it had grounds to terminate Tredrea's services under the Work Health and Safety Act to provide a safe workplace for other employees.

The network had also argued that the presenter behaved in a way that could damage its reputation or business interests.