McGinnis made the All-NBA First Team in his debut season with the 76ers. Teaming up with fellow ABA alumni Julius Erving and Caldwell Jones, McGinnis helped lead the Sixers to the NBA Finals in 1977. McGinnis was traded to the Denver Nuggets in 1978, and was an All-Star again that season. Hoping to boost sagging attendance in their early NBA years, the Pacers re-acquired McGinnis in a trade for a young, high-scoring forward named Alex English. However, McGinnis was only a shadow of his former self, and contributed very little during his two-year return to Indiana. Meanwhile, English went on to become one of the most prolific scorers in NBA history. This transaction is now considered among the worst trades in Pacers' history.