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What happened in the 2003 NBA Finals that has never happened again?

The 2003 NBA Finals market the first—and so far, only—time that both participants were former American Basketball Association teams.

The NBA wasn’t widely considered one of the major American sports leagues until the late 1970s/early 1980s, when the rivalry of Magic Johnson and the Los Angeles vs. Larry Bird and the Boston Celtics elevated the league’s stature and visibility. Prior to that, the U.S. could support more than one basketball league, because none of them were exactly “major league.” The NBA began play in 1946, and in 1967 its biggest challenger came around: the American Basketball Association (ABA).

The ABA was a bit wilder than the NBA, with innovations like a three-point shot (later adopted by the NBA) and a red-white-and-blue ball. It attracted some of the best players of all time, however (to the NBA’s chagrin), including Rick Barry, Julius Erving, George Gervin, and Moses Malone. However, the ABA was financially rickety, and teams changed owners, cities, and nicknames almost every season.

The ABA folded in 1976, as did three of its nine teams: the Utah Stars, San Diego Sails, and Virginia Squires. The NBA bought the remains of the ABA, but only wanted four of the remaining six teams, who had built up big basketball fan-bases in cities where they were no NBA teams. The owners of the Kentucky Colonels accepted a $3.3 million buyout, while the Spirits of St. Louis owners agreed to less money, but a cut of future NBA TV revenues. (Good move: Its earned Spirits owners Ozzie and Dan Silna an estimated $320 million over the years.)

In the 1976-77 season, the four other surviving ABA teams began play in the NBA: the New York Nets (later the New Jersey Nets, currently the Brooklyn Nets), the Indiana Pacers, the San Antonio Spurs, and the Denver Nuggets. It wasn’t until 1999 that any of those teams reached the NBA Finals, when the Spurs defeated the New York Knicks. The championship round of 2003 marked the first time that both Finals participants were from the old ABA. That year, the Spurs defeated the Nets, four games to two.

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