GREATER Western Sydney could face a battle to retain to retain Rory Lobb, with Fremantle poised to make a strong play for the West Australian big man in next month's NAB AFL Trade Period.

This week there has been speculation in Western Australia Lobb has told GWS he wants to return to his home state, but AFL.com.au understands the 25-year-old has not requested a trade and won't have his exit interview with the club until later this week.

Even if Lobb eventually requests a trade, he remains contracted for 2019 and the Giants could insist he honours that deal, especially when he is the No.1 ruckman on a list that has been relatively light on for ruck options since Shane Mumford's retirement at the end of 2017.

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Nonetheless, the Swan Districts product is understood to have struggled with homesickness for much of this season, while Fremantle has been monitoring his situation for some time and will make him a priority target this trade period.

Lobb is believed to earn more than $700,000 a year under his existing contract, which he signed in October 2016 after a stellar season when he was ranked second in the AFL for contested marks behind Gold Coast's Tom Lynch.

Fremantle is expected to offer Lobb a similar salary over a long-term contract.

With veteran Aaron Sandilands and the emerging Sean Darcy on their list, the Dockers can offer Lobb the opportunity to spend the majority of his time in attack as he previously did at the Giants alongside Mumford.

Although West Coast is in the market for a ruckman given Nic Naitanui's long-term injury and Scott Lycett's likely departure to Port Adelaide as a free agent, it is considered unlikely to match Freo's bid for Lobb.

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Lobb is one of several GWS players being targeted by rival clubs, with midfielders Dylan Shiel and Will Setterfield, among others, on the radar of Victorian clubs.

Many in the football industry feel GWS is vulnerable to opposition raids this year as they believe the Giants' salary cap is sufficiently tight that they need to trade a player of Lobb or Shiel's ilk to create breathing space ahead of next season.

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GWS, however, is adamant this is not necessarily the case.

Nonetheless, they face a challenging list management year in 2019, when Shiel, Stephen Coniglio, Nick Haynes, Matt Buntine and Adam Tomlinson will all be in the expansion club's inaugural batch of free agents, and when Lobb, Josh Kelly, Jacob Hopper and Harry Himmelberg will also come out of contract.

Lobb is not due to become a free agent next season because he will have completed just six years' service at Spotless Stadium.

The No.29 pick in 2013's national draft, Lobb has played 74 games for the Giants and kicked 64 goals.