McDonald was delisted after 81 games in six seasons for Melbourne and trained with Carlton throughout the pre-season.

The 24-year-old accepted a contract with the Blues on the last day of the AFL's supplemental selection period.

"It is never an easy situation for a train-on player, however, from the moment Oscar walked into the football club late last year he has done everything possible to earn a spot on the list," Carlton's list manager Nick Austin said in a statement on Tuesday.

"He already has six years of experience at the elite level, has a great work ethic and above all is a great person who will be a welcome addition to the playing group."

Australian Associated Press