Sydney have left out Josh Kennedy and two other key players for their clash with Richmond, giving the Tigers extra cause to believe they they can snatch a last-gasp finals berth at ANZ Stadium on Saturday.

The lure of securing the minor premiership was not enough for the Swans to risk either of their midfield aces Kennedy and Ben McGlynn on the eve of the finals campaign, while Mike Pyke is out due to illness.

Pyke's absence has paved the way for beanpole rookie Sam Naismith to make his senior debut while Sam Reid returns after missing last week through injury. Defender Jeremy Laidler was omitted.

The Swans saw nothing to gain by playing Kennedy and McGlynn in what is essentially a dead rubber for the club, which has already secured a home qualifying final.

"Josh and Benny are just a little bit tight," said coach John Longmire. "I've said all week and particularly after the game, that anyone with any injuries at all, no matter how small they might be, that we were not going to risk them in this game.

"We'd be silly to do that and we didn't want to push them any further than what our medical staff thought they should be pushed today, so we ruled them both out and made that decision early."

Considered a long-term ruck prospect for the Swans, Naismith, 22, has been given a daunting task on debut against in-form Richmond enforcer Ivan Maric.

"He's been going really well in our reserves," Longmire said. "He's 205 centimetres, so he's a young giant, and he's been doing everything we've wanted him to in our reserves, so we've brought him into the team this week.

"Pykey was crook last week and was crook during the game, and he actually wasn't going to play last week, and with the short turnaround he's still catching up with weight. He's been a bit sick, so we thought bringing in Sammy was a good option for us. He's going to be tested against the Richmond rucks who are in really good form."