Aguirre averaged 20 points per game over the course of his 13-year NBA career. He was selected as the first overall pick by the Dallas Mavericks in the 1981 NBA draft and remained with the Mavericks until 1989. In his first season Aguirre was limited to 51 games and averaged 18.7 points, second on the team to Jay Vincent (21.4 ppg). The Mavericks improved by 13 games in the win column and finished ahead of the Utah Jazz, but were still twenty games behind division-leading San Antonio Spurs.