The question is hard to answer, because Thibodeau first arrived in Boston on Aug. 30, 2007, less than a month after the Celtics made their blockbuster trade for Kevin Garnett. We never did find out if the Celtics' defensive greatness during their 2008 title run was the product of Thibodeau's coaching, Garnett's effort, or a combination thereof?
When the Celtics went out and got Thibodeau, Garnett, Ray Allen, James Posey and Eddie House that summer, their identity changed overnight in more ways than one. It's hard to pinpoint exactly what was the Thibodeau effect, and what came from the players.
But Thibodeau did immediately assume the role of "defensive coordinator" when he took over as Doc Rivers' associate head coach, and with it came the task of finding ways to slow down the game's greatest scorers.
Thibodeau mapped out a plan against LeBron James, Kobe Bryant and Dwyane Wade. Stopping the game's greatest players is always a total team effort, and every team needs a leader to run the show.
Who was that leader? Was it Thibodeau, the one mapping out the schemes, or Garnett, the one on the floor barking orders and making plays?
We're about to find out.
The Celtics will be without Thibodeau next season and beyond, as Thibodeau takes a step up after two decades as an assistant, now working as head coach of the Chicago Bulls. Thibodeau gets Derrick Rose, Joakim Noah, Luol Deng and now Carlos Boozer to work with.
The Celtics get a fresh start.
They won't have their defensive coordinator anymore. But they'll still have players that work hard, showing their commitment to playing D and their will to win.
Coaches don't spring to life to contest every single shot, denying the opposing team a single easy look. Players do.
Coaches don't stay in front of their man, move quickly on their rotations and disrupt passing lanes to keep offenses out of sync. Players do.
Coaches don't crash the boards on every miss, working to close out possessions and get stops. Players do.
And at least on the Celtics, coaches don't provide the leadership that fuels the "defense wins championships" mentality.
Players do. It's Garnett, Paul Pierce and Kendrick Perkins, who rarely gets the respect he deserves as one of the best defensive big men in the NBA. It's Rajon Rondo, who uses his speed and his length and his quick hands to become arguably the best defensive point guard alive.
The Celtics have so much talent, so much dedication and so much will that they can't possibly lose sight of their defensive identity.
Tom Thibodeau will be missed in Boston. He's missed everywhere he once left his mark as a defense-first strategist — in Minnesota, in Seattle, in San Antonio, in Philadelphia, in New York, in Houston. And the Bulls are gaining a great coach who knows how to wage war against opposing offenses.
But the Celtics will live on without him. They're too good not to.
NESN.com will answer one Celtics question every day in July.
July 7: Is Doc Rivers' heart still in it?
July 9: Will Danny Ainge make a splash in free agency?
