Boston Celtics: Who might be C’s third-wheel next season?

Boston Celtics (Photo by Carmen Mandato/Getty Images)

Since the Boston Celtics broke back into the playoffs after trading most of the Paul Pierce and Kevin Garnett-led title team, they have been looking (fruitlessly) for a finals appearance. They have made the conference finals three times and have made the playoffs every season since trading for Isaiah Thomas.

Boston has had elite coaching, elite shooting, elite defense, and elite team play for most of these years as they searched for Banner No. 18.

So what’s missing? Why haven’t the Celtics been able to reach the promised land despite having all these good pieces?

It’s simple, really; Boston has rarely been healthy, and they never had a true…