[3] After being drafted in the eighth round by the Seattle Thunderbirds of the Western Hockey League (WHL), Schaefer returned to the OHA Edmonton Elite where he accumulated 24 points through 34 games.

[4] Following his second season with the OHA prep team, Schaefer signed a WHL Standard Player Agreement with the Thunderbirds on September 2, 2018.

[1] Due to the pause, Schaefer played with the Spruce Grove Saints in the Alberta Junior Hockey League (AJHL) during the 2019–20 season, where tallied 6 goals and 16 points while accumulating 32 penalty minutes.

Leading up to the draft, Schaefer drew comparisons to Zack Kassian and was described as having "a legit skill, scoring touch and tenacity" who is destined to be a middle-six winger.

[9] Following the draft, GM Holland praised Schaefer for being a strong competitive big player who could play at the NHL level within two to three years.