Maciver signed as a free agent with the New York Rangers of the National Hockey League on September 8, 1986. Maciver began the 1986-87 with New York, as he made the club after a strong training camp and pre-season. On October 9, 1986, Maciver played in his first career NHL game, recording an assist on a powerplay goal scored by Lucien Deblois in a 5–3 loss to the New Jersey Devils. Maciver would play in four games with the Rangers during the season, earning an assist, as he spent a majority of the 1986-87 season with the Rangers American Hockey League affiliate, the New Haven Nighthawks. In 71 games with New Haven, Maciver scored six goals and 36 points. In seven post-season games with the Nighthawks, Maciver was held to no points.