As a defensive coach, Thibodeau helped the Houston Rockets rank among the Top 5 in the league in scoring defense and field goal percentage defense from 2004 to 2007. He coached in 87 playoff games and was part of the 1999 NBA Finals as an assistant coach with the New York Knicks prior to joining the Boston Celtics, with whom he won the 2008 NBA Championship while serving as an assistant coach. In 2011 he was named the NBA Coach of the Year after leading the Bulls to a 62-win season. In 2012, he became the fastest coach in NBA history to earn 100 victories and finished as the runner-up for Coach of the Year.