Grzelcyk joined the Bruins out of Boston University when he signed a two-year, entry-level deal with the club on April 1, 2016. He competed in his rookie season in 2017-18, playing in 61 games and totaling three goals and 12 assists for 15 points. Grzelcyk skated in 11 postseason games, picking up one assist.
The 24-year-old recorded his first career point on an assist versus the New Jersey Devils on November 22, 2017. Two days later, he notched his first career goal against the Pittsburgh Penguins.
Prior to the NHL, Grzelcyk appeared in 84 games in the AHL with the Providence Bruins, accumulating six goals and 30 assists for 36 points.
The 5-foot-9, 174-pound defenseman won a gold medal in the 2012 U18 World Junior Championship and competed in the World Junior Championship in 2014, scoring two goals and adding four assists for six points in five games.
The Charlestown, Massachusetts native was originally selected by Boston in the third round (85th overall) of the 2012 NHL Entry Draft.
