After going undrafted into the NHL, Schmelzer spent four years playing for the Canisius College Golden Griffins while majoring in management.

While attending Canisius, Schmelzer was named the Atlantic Hockey Best Defensive Forward for 2016–17 and earned NCAA Second All-Conference Team honors.

Upon concluding his senior year, Schmelzer joined the Adirondack Thunder of the ECHL where he set new franchise records for goals and points in the Kelly Cup playoffs.

[4] Growing up in Buffalo, New York, Schmelzer played for the local Amherst Knights program while attending Williamsville East High School.

[1] During the playoffs, Schmelzer and Michael Ederer led the team in scoring with three goals and five assists in their first round series against the Mississauga Chargers.

[13] As the season continued, Schmelzer became a mainstay center on the Griffins top line with wingers Shane Conacher and Ralph Cuddemi.

[19] While the team finished with a winning 21–11–7 record and their first regular season title, Schmelzer also earned numerous conference accolades.

[17] Schmelzer finished the 2016–17 season as the recipient of the Atlantic Hockey Best Defensive Forward Award[20] and NCAA Second All-Conference Team honors.

[22] As team captain, Schmelzer helped guide the Griffs to a second-place finish during the regular season by tallying 13 goals and 17 assists for 30 points.

[24] Upon the conclusion of his senior year, Schmelzer signed an amateur tryout contract with the Adirondack Thunder of the ECHL for the remainder of the 2017–18 season.

[34] While the AHL season was suspended, Schmelzer trained in his home in Fort Erie, Ontario, using propane tanks, water cases, and paint cans as weights.

[42] Under new head coach Kevin Dineen, Schmelzer put up a career high 18 goals and 32 points through 64 games to rank sixth on the team in scoring.

[3] As the Comets finished the regular season as the AHL's North Division champions, they earned a bye in the Calder Cup playoffs[43] and met with the Americans in the second round.

[10] After finishing the 2023–24 season with a career-high 18 goals and 34 assists, Schmelzer signed a two-year, two-way contract with the New Jersey Devils on April 30, 2024.