The San Diego Conquistadors, nicknamed the "Q's", were an American Basketball Association team based in San Diego, California. They were the only expansion team in the history of the ABA. The team started play in the 1972-1973 season.

The franchise was founded by Leonard Bloom at the same time a modern facility opened in the city: the 14,400-seat San Diego Sports Arena. But a feud between Bloom and Peter Graham, proprietor of the city-owned arena, led Graham to lock the newborn team out of the facility for two years. By the time the conflict was resolved in the fall of 1974, it was too late for a weakened franchise that had been forced to play, in the interim, at such bandboxes as Peterson Gym (3,200 seats) and Golden Hall, a mere ballroom.

After reaching the playoffs in their inaugural season, the Q's seemingly pulled off a coup by paying the Hall of Fame center Wilt Chamberlain, late of the Los Angeles Lakers, $600,000 to play and coach in 1973-74. But the Lakers sued to block their former star from playing for his new team; relegated to a sideline role, Chamberlain was reduced to an indifferent, 7-foot-1-inch sideshow who once skipped a game in favor an autograph session for his recently published autobiography. (His fill-in, on that and other occasions, was Stan Albeck, who later skippered the Chicago Bulls and New Jersey Nets of the NBA.) Nonetheless, the team again reached the postseason, bowing out in the first round for the second year in a row.

For their third season, 1974-75, the Q's lost Chamberlain and finally gained their place in the Sports Arena. But without the Big Dipper as a gate attraction, the team was roundly ignored by San Diegans and placed last in the Western Division.

Bloom sold the franchise during the summer of 1975 to Frank Goldberg, a former co-owner of the successful Denver Nuggets franchise. He renamed the team the San Diego Sails for 1975-1976, hired the former University of Minnesota coach Bill Musselman and overhauled the roster, hoping to repeat Denver's turnaround, in 1974-75, from mediocrity to championship contender.

But the Sails attracted only 3,060 fans to their home opener on Oct. 24, 1975 - a loss to the Nuggets - and fan attendance rapidly dwindled further as the team limped to a 3-8 start. (A "crowd" of 1,670 showed up for San Diego's third and last home game, against the San Antonio Spurs.) Goldberg soon learned San Diego was to be shut out of any merger between the ABA and National Basketball Association, reportedly at the insistence of the Lakers owner Jack Kent Cooke, who refused to share his Southern California fan base with a team to the south.

With the team lacking fan support or a long-term future, Goldberg euthanized the franchise on Nov. 12.

The collapse of the San Diego team, combined with the failures of the Baltimore and Utah franchises, reduced the ABA to seven franchises and effectively signed the league's death warrant, though the NBA absorbed four of the surviving squads in the summer of 1976.