The 18-year-old Cobden export, who was named the round four NAB AFL Rising Star nominee after 28 disposals and one goal against Gold Coast, signed a two-year extension and will remain at the club until at least the end of the 2022 season.

The midfielder's signature is a show of faith in the direction the club is taking despite a winless start to 2019.

Walsh joins co-captain Pat Cripps (2021), Zac Fisher (2021), Sam Petrevski-Seton (2021) and Paddy Dow (2022) as players in the Blues' blossoming midfield who have committed to the club.

Walsh - who is averaging 26 disposals, 12 contested possessions, five clearances and three tackles after four games - said he immediately felt welcomed into the club.

"The coaches, staff and entire club provide us with everything we need to get the very best out of ourselves, which I have loved. It just motivates you to get better every day," he said.

"What struck me straight away was the elite standards our Club has in place, driven by 'Crippa' and 'Doc' (co-captain Sam Docherty). That has us focused as a young group to fast-track our development and achieve success together."

Blues List Manager Stephen Silvagni was impressed by Walsh's immediate professionalism.

"We could not have asked much more of Sam with the way he has approached his football from the moment he walked through the door," he said.

"From that day on his sole focus has been to make himself the best player he can possibly be for the Carlton Football Club.

"He is an impressive young player and a really quality person so we are delighted Blues fans can now watch Sam and our young midfield develop together into exciting players for Carlton over the next few years."

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