Maciver began the 1990-91 season with Cape Breton. In 56 games in the AHL, Maciver scored 13 goals and 59 points before being recalled to Edmonton in February. On February 24, 1991, Maciver earned his first points with the Oilers, as he had two assists in a 6–3 win over the Quebec Nordiques. ON March 24, 1991, Maciver scored his first goal with Edmonton against Kelly Hrudey of the Los Angeles Kings in a 4–3 loss. In 21 games with Edmonton, Maciver scored two goals and seven points. On April 4, 1991, Maciver appeared in his first post-season game with the Oilers, as he had no points in a 3–1 win over the Calgary Flames. In the seventh game of the series against the Flames, Maciver earned an assist for his first career playoff point, as Edmonton defeated Calgary 5–4 to win the series. In 18 playoff games, Maciver earned four assists.