Blair's commitment follows a string of re-signings for the club this season, including Ben Reid, Steele Sidebottom, Nathan Brown, Dane Swan, Heritier Lumumba and Brodie Grundy.
It is a boost for the club as it fights for a finals position after its 10-goal loss to West Coast. It was the Magpies' sixth loss in their past eight games.
"We didn't bring enough intent at the contest, we didn't bring enough work rate, we weren't prepared to roll the sleeves up," Buckley said.
"And when I say, 'we', [I mean] every player. [I did] a quick straw poll of our playing group then against our trademark – attitude and effort – who's going to give themselves a tick? No hands. Zero hands. First time all year.
"To a man, all of them felt that they let the team down and you get a result like that."