In his draft-eligible season with the Remparts in 2021–22, Gaucher, was awarded the Michael Bossy Trophy as the QMJHL's Best Professional Prospect after scoring 31 goals and 26 assists for 57 points in 66 games.
[6] Gaucher managed 7 goals and 9 assists in 18 playoff games as the Remparts advanced to the QMJHL Finals and won the Gilles-Courteau Trophy, the franchise's first league championship in 47 years.
[7][8] As QMJHL champions, the Remparts were the league's representatives at the 2023 Memorial Cup in Kamloops, playing against the host Blazers, the Peterborough Petes, and the Seattle Thunderbirds.
[7] The Remparts ultimately defeated the Thunderbirds in the Memorial Cup final, taking the championship for the third time in team history.
[9] Gaucher was named to Team Canada for the COVID-delayed 2022 World Junior Ice Hockey Championships, winning gold.