Momesso was drafted by his hometown, the Montreal Canadiens, in 1983, after playing in the QMJHL for two seasons. In his 1984-85 season, Sergio was named player of the year in the QMJHL, recording 56 goals, and 146 points in 64 games with 216 penalty minutes. He made his debut with the Canadiens in the 1983-84 season although he only played one game in the NHL until 1985-86. Sergio went on to play with the Canadiens for 4 seasons, then the Blues, Canucks, Leafs, Rangers, and played the end of his career in the DEL. His NHL stats consist of 711 games, 152 goals, 193 assists, 345 points and 1557 pim. Since his playing career, he began a career in the media space, doing commentary for the Montreal Canadiens hockey, working for CJAD, and now with TSN.