SYDNEY Swans youngster Luke Parker is backing fellow midfielder Ryan O'Keefe to bounce back strongly after the veteran was initially left out of the season-opening side to face Greater Western Sydney.

O'Keefe was a surprise omission from the original side named before ultimately earning a reprieve after Kieren Jack was ruled out on game day with a back issue.

The 33-year-old, who is fourth on the Swans' all-time games played list with 283 appearances, fell behind the likes of Tom Mitchell, Harry Cunningham and Parker himself for a spot in the club’s deep midfield over the pre-season.

O’Keefe seemed intent on making a point on Wednesday, staying back well after every other player and official had left the training track to run laps on his own, before declining interview requests.

The Swans have a weekend off before facing Collingwood in round two, when Jack is expected to be fit and – barring injuries – O'Keefe will once again have to battle for a spot in the line-up.

But 21-year-old Parker is confident his teammate, a Norm Smith medallist and former All Australian, has plenty left to give.

"Definitely. He was sub on the weekend and I'm sure he'll be back this season and play some really good footy for us," Parker told reporters.

"For Ryan it was pretty disappointing (being initially left out of the team).

"It's up to the coaches to pick the team, but for us it shows how much depth we do have.

"I wouldn’t want to be in the coaches room picking the team.

"I think there's only two or three people they can't pick (due to) injuries, so I wouldn't have fun putting the team together."

The Swans were confronted with a difficult review of their performance against the Giants, with Parker making the damning assessment that the young GWS line-up had simply "wanted it more".

Parker also said the Swans' reduced pre-season, due to their progression through to the preliminary finals, wasn't a factor.

"We had more practice games than we've ever had before and we showed up on the day and just didn't play four quarters," he said.

"It's as simple as that. We played a half and got smacked around stoppages in the last quarter.

"They just attacked it and wanted it more.

"The first half wasn't too bad, but our contested ball in the last quarter was minus-19 and we know that's a stat that wins games.

"They got their enthusiasm up and we didn't go with them.

"We have pretty high standards and a trademark we live by and we didn't show up ready to play."

Parker admitted he would prefer the Swans had a game on this weekend to give them a chance to quickly atone for their poor display.

He also knows it will be a high-stakes game against a Pies outfit that suffered a heavy round-one loss to Fremantle.

"Personally I'd rather play this week and be able to turn it around," he said.

"But having the two weeks off we can freshen up, get our mindset right, focus on what happened on the weekend and the boys have moved on today.

"It is going to be pretty desperate for both teams. We don't want to go zero-and-two.

"The boys trained well today, we've got another two weeks of training and we'll prepare as well as we can for that game and hopefully bounce back."

Twitter: @AFL_JD