Prior to tip, a Celtics official told CSNNE.com's Jessica Camerato that Rondo was at the hospital receiving an MRI after treatment in the morning didn't help with the point guard's recovery.
Chris Forsberg of ESPN reports that Courtney Lee is listed as the replacement in the starting lineup, meaning he and Avery Bradley will man a backcourt lacking a true point guard.
Furthermore, the news kills at least two storylines. The tension between Boston and Miami was to be heightened by the return of guard Ray Allen to the TD Garden, and Rondo was the key player in the former Celtic leaving for the rival Heat. Missing the game on Sunday also dissolves the opportunity for Rondo to record his third triple-double in a row. It would have been the first time in four years that an NBA player recorded three straight triple-doubles.