St. Lawrence University Athletics

Prior to St. Lawrence

A native of Ottawa, Ontario, Posthumus played prep school hockey at Peak Academy, where he also participated in a variety of sports and was on the school's honor roll…Standing at 6-0, the right-shot forward began his junior hockey career with the Nepean Raiders of the CCHL where he was named the CCHL Rookie of the Year along with Academic Player of the Year honors... He played in 60 games for the Raiders, scoring 20 goals and assisting on 29 for 49 points...Posthumus moved on to the Tri-City Storm of the USHL in 2023-24, where he had three goals and ten assists in 38 games, then had 46 points on 25 goals and 21 assists in 2024-25 with the Penticton Vees...The forward was in the OHL as a member of the Oshawa Generals this past season, skating in 67 games, scoring 23 goals and adding 34 assists for 57 points.