BACK-to-back premiers Hawthorn's focus will be on getting into "good habits" against a severely undermanned Carlton on Saturday, veteran defender Grant Birchall says.

The Blues – pummelled by a club record 138 points by the Hawks in round 17 – could have just 25 fit players to pick from for retiring midfielder Andrew Carrazzo's final match at the MCG.

But Birchall said the Hawks needed to keep sharpening their form at the pointy end of the season ahead of a likely trip west for a qualifying final, and he wasn't concerned about what Hawthorn's opponents serve up in round 23.

"They've still got some quality players (and) it's Carrazzo's last game, so they'll be up for that," he said.

"We just want to get into some really good habits and play some good footy, some good consistent four quarters of footy leading into finals.

"I think we've been playing some reasonable footy. I think we'll focus on our starts to games – particularly this week it will be a bit of a focus – so I think we're building quite nicely."

Competition for spots is heating up and keeping the Hawks on their toes, with Birchall confirming Sam Mitchell (illness) and Paul Puopolo (ankle) would be fit to face the Blues.

Meanwhile, premiership backman Matt Spangher (hamstring) returned from a lengthy stint on the sidelines for Box Hill last weekend. 

"We've pretty much got a full list to choose from. We made top four, which was a goal for us at the start of the season, so I think we're in pretty good shape, we'll just take it week by week," Birchall said.

The Hawks experimented with James Frawley (three goals) playing in attack in a 72-point belting of the Brisbane Lions last weekend, showcasing another string to the ex-Demon's bow ahead of his maiden finals campaign.

"It was great to see 'Chip' go up forward and kick a few goals and create some really good contests for us and if need be can down back and play a role as well," Birchall said.

"It's great to have players like that in our side and it creates good competition for spots, which is healthy for us."

That competition could drive the Hawks to a premiership three-peat, with Birchall declaring the chance to create history is motivating him.

"Yeah it does, it would be a fantastic achievement if we can do it, but there's a lot of water to go under the bridge and we'll just focus on this week," he said. 

"It would be amazing, I never thought in my wildest dreams I'd win three or four flags.

"So we'll just do as best as can and prepare as hard as we can to achieve that, but there's a long way to go yet."

In other news, understands speedy midfielder Billy Hartung is making solid progress in talks about a contract extension after playing 18 games in his second season.