GREATER Western Sydney ruckman Sam Jacobs has cut short his two-year contract with the Giants after opting to retire immediately.

Jacobs informed his teammates after the Giants' season-ending loss to St Kilda on Friday night, having missed selection for the second straight week. 

WHO'S LEAVING? Your club's retirements and delistings

Jacobs crossed from Adelaide ahead of the 2020 season and managed just seven games for the Giants this season with veteran Shane Mumford (10 games) proving coach Leon Cameron's preferred option. 

The 32-year-old leaves with 208 AFL games to his name after stints at Carlton (2009-10), Adelaide (2011-2019) and the Giants in 2020. 

Sam Jacobs farewells Adelaide fans after round 22, 2019. Picture: AFL Photos

"Things didn't quite go to plan this year and I got out with real happiness and I'm really proud of the career. I've been very lucky to be part of three great clubs," Jacobs said. 

"With our second child due in November, it's time to put my family first and it just feels like the time is right and I'm really excited about what's next. 

"As footballers, we live a very stressful life at times and you can't switch off and I honestly feel like I haven't switched off for 14 years. 

"I've made lifelong friends at the three clubs I've been fortunate enough to play at and I thank them all for the opportunity." 

Sam Jacobs celebrates a goal against Adelaide in round 16, 2020. Picture: Getty Images/AFL Photos

Jacobs' decision to retire leaves the Giants with a ruck headache approaching 2021 which is expected to force them to look elsewhere. 

Mumford, 34, remains without a contract to play on next season, with the ruck division also consisting of untried pair Matthew Flynn and Kieren Briggs. 

"Sam had a big impact on our club in a short space of time and we thank him for his contribution over the past 12 months," Giants head of football Jason McCartney said.

"We wish Sam, his wife Isabelle, daughter Imogen and baby Jacobs all the best for their future back in Adelaide."