Collingwood's decorated midfielder Dale Thomas is set to join Carlton as a free agent, with the Blues about to secure him on a four-year deal worth close to $700,000 a season.

Thomas, a 2010 premiership player, 2011 All-Australian and one of the most popular Collingwood players, will exercise his right as a restricted free agent and nominate the Blues as his preferred club.

Collingwood's Dale Thomas is on the move. Credit:Sebastian Costanzo

The Magpies were uncertain late on Thursday whether Thomas would attend the club's best and fairest on Friday night. Thomas had indicated he would attend the Copeland Trophy on Wednesday, but this could be re-considered, given that the Blues could lodge the contract with the AFL today - and, in effect, Thomas would be attending the function as a Carlton player-in-waiting.