The 26-year-old is joining the Blues as a delisted free agent after playing 155 games for the Saints.

"It has been a bit of a whirlwind the last couple of months but I'm glad the decision has been made," he said on Friday.

Newnes will bolster the midfield stocks at Carlton and offer experience after spending four years in St Kilda's leadership group.

"I think there are a lot of young players here and I have got a lot of experience so hopefully I'll be sharing a bit of knowledge about what it takes," he said.

"I have got a lot of improvement in my game personally; I haven't yet reached the highest level I can.

"So I am really excited to push myself and push the group as well."

Carlton's list manager Stephen Silvagni said Newnes' maturity was appealing to the Blues.

"Jack has been in the system for eight years, he is a mature body ... we think he can strengthen our playing list," Silvagni said.

"He is an elite runner who will add another dynamic for us through the middle of the ground."

Port Adelaide have also moved quickly in the delisted free agency period, signing ex-Geelong forward Wylie Buzza on Friday.

Buzza, pick 69 in the 2015 draft, played nine AFL games for the Cats but none last season.

The delisted free agency period ends on November 22.

Australian Associated Press