But he reckons it's set for an almighty rattling on Friday night against the freewheeling Western Bulldogs at Adelaide Oval.
Carr is unashamedly building from the back - his Power are ranked fourth-best for points conceded.
"It's a work in progress. It's not perfect, we're still chipping away at it and trying to get better," he told reporters on Thursday.
"It definitely keeps us in a game and it's definitely a great foundation to start from.
"It's always nice to have a defence that defends really well but moreso a team that can help out and we've probably been consistent in that area."
Port (three wins, five losses) hold 13th spot ahead of hosting the 12th-placed Bulldogs, on a four-match losing skid and battered by injury.
Yet Carr is bracing for an aggressive approach from the Dogs, who have gone from premiership fancies to after-thoughts amid a heavy injury toll.
"There are some guys that can use the footy in their back half, Bailey Dale's elite with his ball use," he said.
"They're quite aggressive from the D50. So it's an opportunity for us to get our team D right, but on the other side of that we make sure we use the footy."
Bulldogs coach Luke Beveridge revealed mid-week captain and star playmaker Marcus Bontempelli was carrying knee and heel injuries.
"We prepare for him to play and if he doesn't, it's definitely a bonus," Carr said.
"I don't think you can stop him. We've tried a few things on him over the years with a tag and not a tag, and had some success in both.
"And then we've also not had success with him getting off the chain.
"So we know what sort of player he is - even when he's not getting the ball, he's an influence on his teammates."
11°C