MELBOURNE has scratched another key player off the free agency list, with gun defender Neville Jetta extending his contract for a further three seasons. 

The new contract will see Jetta, who was an unrestricted free agent, remain at the Demons until at least the end of the 2021 season. 

Jetta's signature follows that of restricted free agent Tom McDonald who committed to the club for another four years early last month. 

"We are delighted that Nev has agreed to a new three-year extension," Demons football manager Josh Mahoney told melbournefc.com.au.

"Nev has been a consistent performer for us, for a long period now and is a great example of resilience and maximising opportunities. 

"A three-year deal is great reward for Nev's commitment to our club." 

The 28-year-old has managed 132 matches since making his AFL debut in 2009.

After being delisted in 2013 and then put back on the rookie list the following year, Jetta has become one of Melbourne's most dependable players and in the process made himself one of the AFL's top small defenders. 

With Jetta and Tom McDonald inking new deals, the Demons will look to re-sign Tom's younger brother Oscar in the coming weeks.

Oscar, who has become Melbourne's No.1 tall defender, told AFL.com.au recently he would love to remain at the club in the long term.

"We're in talks at the moment. I don't know how far along it will be until I sign but I'm really confident that I'll sign with the club," McDonald said.

"I'd definitely love to be a one-club player at Melbourne."