Harrison, 19, skated in 65 games with the Oshawa Generals of the Ontario Hockey League in 2021-22, totaling 27 goals and 34 assists for 61 points. The London, Ontario native added four goals and three assists for seven points in six OHL playoff games.
The 6-foot-2, 185-pound forward appeared in 58 OHL games with Oshawa in 2019-20, recording 21 goals and 16 assists for 37 points.
Harrison was originally selected by Boston in the third round (85th overall) of the 2021 NHL Entry Draft.