The Trail Blazers said Lucas died Sunday.
Lucas, whose No. 20 was retired by the Blazers in 1988, joined Portland in the 1976 ABA dispersal draft and led the 1976-77 championship team in scoring with a 20.2 average. He also averaged 11.2 rebounds that season.
The former Marquette player averaged 14.4 points and 8.8 rebounds in 12 NBA seasons with Portland, New Jersey, New York, Phoenix, the Los Angeles Lakers and Seattle. In two seasons in the ABA with St. Louis and Kentucky, he averaged 15.2 points and 10.8 rebounds. He also served as an assistant coach with the Blazers.
Lucas led Marquette to the 1974 NCAA title game against North Carolina State and was selected to the All-Final Four team along with future Portland teammate Bill Walton. The 6-foot-9 former Pittsburgh high school star averaged 15.8 points and 10.6 rebounds that season.
Walton named son Luke, a player for the Lakers, after Lucas.