ROBBIE Gray trained lightly and only indoors on Tuesday, but Port Adelaide skipper Travis Boak remains hopeful the club will regain the All Australian midfielder’s services for Sunday's Showdown.

Boak sat alongside his Adelaide counterpart Taylor Walker at Adelaide Oval on Tuesday afternoon, and said Gray's confidence in his corked calf was improving.

Gray will undergo a fitness test on Thursday after he was withdrawn from the Power's side that beat Hawthorn last weekend.

"I spoke to him today and he said he's feeling a lot better. Obviously at this stage he's still touch and go and we'll wait and see," Boak said.

"[He'll] probably train Thursday and see how it feels. He can't really do too much until then.

"We're hoping to get him back for the game on Sunday."

Jared Polec also trained indoors on Tuesday after being subbed out of last Saturday night's win.

The speedy left-footer began the week in a moonboot with a foot injury that he's been forced to carry through the past two games.

Boak insisted he'd be "fine" to take his place in the Power's line up.

Adelaide has selection issues of its own, with Walker flagging the possible inclusion of Kyle Cheney to deal with the Power's potent attack.

Jay Schulz was on fire against the Hawks with five goals, Patrick Ryder was brilliant and Justin Westhoff is a known Showdown performer.

Westhoff has averaged more than five marks and 14 possessions a game in his 14 Showdowns and has kicked 23 goals.

The Crows' conceded their largest score of the year last weekend against the Western Bulldogs (125 points) and had no answer to Jake Stringer, who bombed six majors.

Walker said the club's defence – which had conceded fewer points than any side prior to round three – was let down by the players up the field.

He said a lack of team defence around the ground made it difficult for the back six to contain the Bulldogs' forwards.

Cheney has missed the past two games with a hamstring injury but would be a likely inclusion should he prove himself fit at training this week.

"It's not just the back six, it's the 18 guys on the field – we pride ourselves at the Adelaide footy club on the 18 blokes on the field being able to defend as a team," Walker said.

"They've got some good talls up there, Schulz kicked five on the weekend – Kyle Cheney, he'll put his hand up for selection.

"We've got Kyle Hartigan, Daniel Talia, we've seen what Jake Kelly can do - he's a fierce competitor.

"I'll leave that up to 'Dasha' (defence coach Darren Milburn) and the coaches, but I think Kyle Cheney will put his hand up."