The 1990 NBA Finals was the championship round of the 1989-90 NBA season. The series pitted the Detroit Pistons (the previous year's champions) against the Portland Trail Blazers. The Pistons became the just the third franchise in NBA history to win back-to-back championships, joining the Los Angeles Lakers and Boston Celtics. Renowned Pistons announcer George Blaha narrated the season-ending documentary "Pure Pistons" for NBA Entertainment, with MC Hammer's "U Can't Touch This" being the closing song.