Boston sent a 1971 fifth-round pick to San Diego for Art Williams, turning the No. 78 selection that became Greg Nelson into four seasons of useful reserve point-guard play. Williams appeared in 303 regular-season games for the Celtics, posted 11.1 win shares in that span and remained on the roster through Boston's 1974 championship season. Nelson was drafted by the Rockets at No. 78 but never appeared in an NBA game. The low acquisition cost and durable rotation value make this a clear Celtics win.
On September 10, 1970, the San Diego Rockets traded Art Williams to Boston for the Celtics' 1971 fifth-round draft pick. Basketball-Reference records the same transaction on the Celtics, Rockets and league transaction pages, while the executive histories for Red Auerbach and Pete Newell independently preserve the deal. The pick became the No. 78 selection in the 1971 draft, which the Rockets used on Jacksonville forward Greg Nelson.
Williams was not acquired to become a star, but Boston received far more than a one-season rental. He played 74 games in 1970-71, then 81 in each of the next two seasons and 67 in 1973-74. Across four Celtics seasons he appeared in 303 regular-season games and Basketball-Reference credits him with 11.1 win shares. His best Boston season by raw production was 1971-72, when he averaged 5.1 points, 4.0 assists and 3.2 rebounds in 16.4 minutes per game. He remained part of the roster when the 1973-74 Celtics went 56-26 and won the NBA championship.
San Diego converted Williams into a late draft asset rather than losing him for nothing. The pick landed at No. 78 overall in the fifth round, and the Rockets selected Greg Nelson out of Jacksonville. Nelson never appeared in an NBA game, so the pick produced no realized NBA playing value. That outcome matters because the comparison is not between Williams and an abstract future pick anymore; the asset can be traced to a specific selection and player. The low round softens the opportunity cost, but the Rockets still moved a useful veteran and received no NBA production from the draft outcome.
The scale of the deal is modest, yet the result is unusually straightforward. Boston surrendered a fifth-round pick that became a non-NBA player and received four seasons from a dependable reserve guard. Williams was never one of the Celtics' primary scorers, but his 303 games, positive win-share total and role through the 1974 title season represent substantial realized value for the price. San Diego's pick outcome never reached the league. That makes the trade a strong example of a contender extracting practical roster value from a low-cost future asset rather than a franchise-altering blockbuster.
Celtics Win, B+/D+. Boston earns a B+ because a fifth-round pick became four years of useful guard depth, including a place on the 1974 championship roster. The Rockets receive a D+ because the No. 78 pick was correctly preserved and used, but Greg Nelson never played an NBA game and the asset produced no realized league value. Confidence is high: the transaction date, compensation, draft outcome and Williams' Boston production all agree across Basketball-Reference's team, league, executive, player and draft records.