SYDNEY Swans coach John Longmire faces the incredibly difficult task of trying to keep his side focused on Saturday's clash with Geelong following the tragic death of co-captain Jarrad McVeigh's daughter.

Jarrad and Clementine McVeigh's daughter Luella passed away on Wednesday afternoon from a serious heart complication she had battled since she was born on July 25.

Swans co-captain McVeigh will miss the trip to Skilled Stadium and it is not known when he will return to the field.

The news has obviously devastated everyone involved with the club and Longmire faces the near-impossible job of keeping his players' minds on the job in an important game for the Swans' season.

Longmire said everyone had learned a great deal from the way McVeigh performed last week, when he was one of the Swans' best players in their victory over St Kilda.

"Jarrad gave us all a really good lesson last week about worrying about what you can control and focusing on the moment," Longmire told reporters ahead of training at the SCG on Thursday.

"I think we've all taken something out of that, either as players or coaches, to make sure we focus on the moment.

"We support Jarrad and Clementine as much as we can, we then come to training today and focus on preparing as best we can and head down to Geelong tomorrow and face a formidable opponent at their home deck, which we're really looking forward to."

The players will wear black armbands when they face Geelong in a game that will help decide the Swans' finals fortunes.

The seventh-placed Swans face the Cats and then host the Brisbane Lions at the SCG the following week in their final home and away game.

The Swans are a close-knit unit and co-captain Adam Goodes, plus fellow veterans Jude Bolton and Ryan O'Keefe, will have an important role helping the side prepare to face the Cats.

But Longmire expects all his players to stand up and play their role under extremely difficult circumstances.

"I think Adam's been exceptional at doing that this year anyway," Longmire said when asked the importance of Goodes' leadership during this time.

"But it's not just Adam, it's about everyone making sure they pull their weight and I'm sure that'll happen.

"We've got a very strong group of players here that are able to focus on the moment and look forward to playing Geelong in Geelong.

"It's one of the great challenges in footy and that's our test this week, to go down there and put our best foot forward and be as competitive as we can."