Boston acquired Bob McAdoo from New York on February 12, 1979 for Tom Barker and three 1979 first-round picks that became Bill Cartwright at No. 3, Larry Demic at No. 9 and Sly Williams at No. 21. McAdoo played only 20 games for Boston, but the Celtics moved him to Detroit that September for two 1980 first-round picks. Boston then traded those two picks to Golden State for Robert Parish and the No. 3 selection used on Kevin McHale. New York received a major direct return, led by All-Star center Cartwright plus useful years from Demic and Williams, but Boston's McAdoo branch ultimately produced two franchise pillars and multiple championships.
Boston's February 12, 1979 transaction sent Tom Barker and three 1979 first-round picks to New York for Bob McAdoo. The picks became Bill Cartwright at No. 3, Larry Demic at No. 9 and Sly Williams at No. 21.
Cartwright started all 82 games as a rookie, averaged 21.7 points and 8.9 rebounds and made the All-Star team. He remained a major Knicks center through the first half of the 1980s before a foot injury wiped out 1984-85. Demic also gave New York three full seasons. He played 206 games, including all 82 as a rookie, and started 68 times across his Knicks career. Williams played 57 games as a rookie, then became a starter in 1980-81 and remained a productive forward into 1981-82. Barker added 22 games immediately after the trade. The Knicks therefore converted McAdoo into several years of direct roster value, not just draft capital that failed to develop.
McAdoo played 20 games for Boston after the trade. He scored 411 points, averaging 20.6 points and 7.1 rebounds in 31.9 minutes. On its own, that would not justify surrendering three first-round picks. The downstream transaction is what transforms Boston's side.
On September 6, 1979, Boston traded McAdoo to Detroit for two 1980 first-round picks. Basketball-Reference notes that the exchange was arranged as compensation connected to Boston's signing of M.L. Carr. Those picks later landed at No. 1 and No. 13 in the 1980 draft. Boston did not make either selection. On June 9, 1980, the Celtics sent both picks to Golden State for Robert Parish and the No. 3 pick.
The next day, Boston selected Kevin McHale with the third pick. Parish and McHale became two core pieces of the Celtics teams that won the 1981, 1984 and 1986 NBA championships. Because the McAdoo-to-Detroit and Detroit-picks-to-Golden-State steps are both direct transactions, this branch has much stronger attribution than a chain that requires several unrelated assets. Boston's McAdoo acquisition is therefore a legitimate upstream part of the Parish-McHale outcome.
A hindsight win for Boston does not make the Knicks' return poor. Cartwright became an All-Star-level starting center, Demic supplied 206 games and Williams developed into a productive starter before leaving New York. The difference is ceiling. Boston turned a 20-game McAdoo stint into two first-rounders and then directly converted those picks into Parish and McHale.
Celtics Win, A+/A. Boston receives an A+ because the McAdoo branch produced Parish and the pick used on McHale after two direct follow-up trades. New York receives an A because Cartwright became a long-term starting center and All-Star while Demic, Williams and Barker added substantial immediate roster value.