The Brisbane Lions have finally secured key defender Jack Frost from Collingwood.

Frost nominated the Lions as his preferred club just days after the AFL Grand Final but it took until the final hour of the NAB AFL Trade Period to get a deal done with Collingwood.

The Lions receive Frost, pick No.76 and a 2017 third-round selection in exchange for a third-round and fourth-round pick in the 2017 NAB AFL draft.

Pick No.76 was on-traded by Collingwood after the Magpies received it from the Western Bulldogs in exchange for Travis Cloke.

Frost moves north in search of more opportunities at AFL level. He played 22 games in 2014 and 20 games in 2015 after being drafted as a rookie in 2013.

But he managed just 10 games for the Magpies in 2016 and did not play after round 12.

Frost played 54 games for Collingwood in four seasons overall.

Lions list manager Peter Schwab said Frost would help fill the hole left by retired defender Daniel Merrett.

"With Jack, all year we've been tracking key defenders," Schwab told lions.com.au.

"At 24, even though he's only had a little experience he's still got plenty of football ahead of him.

"He's got great speed and is a good character, he's a perfect fit." 

Frost has signed a three-year contract with the Lions.