On January 10, 2007 Tony Allen blew out his left knee in a post-whistle slam dunk. Two years later, he still isn’t the same player.

At the time of his injury Allen was one of the few bright spots on a dismal Boston Celtics team. He had stepped up in the absence of Paul Pierce and was doing his best to lead his team with explosiveness and  defensive hustle. He was also averaging a career high 11.5 points, 3.8 rebounds, and shooting 51.4% from the field. In an instant, it was gone.

Reminders of Allen’s injury have come to mind with the recent struggles of the Celtics bench. He has missed the last three games with an ankle strain and has been inconsistent when healthy. Allen, who turns 27 on Sunday, has learned to accept his role as a defensive specialist. At times there are flashes of the old TA, slashing to the basket, getting up for a dunk, or attacking the hoop for a rebound. But those highlights have been few and far between.

On the date of his injury it’s easy to wonder, what if Tony Allen never went up for that dunk?

If Allen had continued his breakout season, he most likely would have been packaged in the Ray Allen trade instead of Delonte West. If not, the Minnesota Timberwolves probably would have pushed for him in the Kevin Garnett deal. Allen was playing too well to stay on a team desperate to make moves.

There would be no need to wonder what if. Chances are Tony Allen wouldn’t be on the Celtics.