Here's a look at the voting breakdown:
The 2017 first-round pick made his much-anticipated debut in the playoffs last year and came through with a game-winning goal in his first appearance and five assists over the next nine games. He carried this level of play into the regular season with 50 points in 57 games. He was one of seven defensemen regardless of age with at least 50 points, ranking second among rookies behind only Hughes.
What separated Makar was his production in fewer games, averaging 0.88 points per appearance.
The Avalanche star also finished plus-12 on the season compared to Hughes' minus-10, making a significant impact on both ends of the ice.
Makar immediately jumped into a big role with Colorado, averaging more than 21 minutes on the ice per game. The 21-year-old was also second on the team with 38 assists, trailing only 2013-14 Calder Trophy winner Nathan MacKinnon.
The Canadian helped the Avalanche become one of the best teams in the league this season with 92 points in 70 games. His level of play and impressive production made Makar the top rookie in the NHL, and he became the first defenseman to win this award since Aaron Ekblad in 2014-15.