SYDNEY key defender Heath Grundy is no guarantee to return for Friday night's crucial clash with Essendon as coach John Longmire continues to weigh up the veteran's place in his best side.

After being rested for the Swans' win over North Melbourne in round 17, there were plenty of questions asked when Grundy wasn't brought straight back into the 22 to face Gold Coast on Saturday.

The 32-year-old instead lined up in the NEAFL in a 10.30am kick-off against the Suns and was forced to look on from the stands as the senior side coughed up a 29-point quarter-time lead to lose to the visitors at the SCG.

Grundy had 25 possessions and took five marks in his first reserves game since 2008.

A lack of leg speed is his greatest weakness which could be an issue against the quick Bombers forward line this week, but his experience and cool head deep in defence could be critical, especially with Jarrad McVeigh (collarbone) also missing. 

Longmire said Grundy's recent form and a lack of suitable opponents in the Suns' side were factors in him coming back through the reserves, and those things will be looked at again this week. 

"It's always a combination of both," he said on Monday. 

"He had a couple of quiet ones before we rested him and we're working through a couple of those things, so it's a combination of that and match-ups (available)." 

Grundy is out of contract at the end of the season and while he's keen to play on in 2019, his omission so late in the season with finals just around the corner casts serious doubt on his career. 

Longmire said the club will sit down with Grundy as well as McVeigh, who is in the same position as his fellow backman, to discuss any future plans, but that will likely be later in the year and possibly could come after the season. 

"It might happen before then but it's not at the forefront of our minds because clearly we've got to pick ourselves up and play better than we did last week," he said. 

"We'll sit down at the appropriate time and that will evolve.

"At the moment we're on a six-day break ahead of (playing) Essendon on the weekend so now isn't the right time to do it." 

The Swans copped some more bad news on the injury front with forward Gary Rohan breaking his hand in the reserves on Saturday. 

Rohan will have surgery to have a plate inserted on Monday, with Sydney yet to find out how long he'll be out for. 

He joins McVeigh, Kieren Jack (knee), Dan Hannebery (calf), Sam Reid (Achilles), Callum Mills (foot) and Sam Naismith (knee) on the list of Swans absentees.