But in a bit of good news, ESPN's Adrian Wojnarowski reports that the team believes the left knee soreness hampering star Kyrie Irving is not serious.
Shortly after this, Shams Charania of The Vertical reported the tendon was torn, and that Smart will be seeking a second opinion.
Irving is expected to miss the entire week as he manages a sore knee.
Arun Jaitley files nomination for RS poll
The infighting in the Gujarat unit of the Congress came to fore with party leader P K Valera entering the fray as an independent. The main Opposition RJD fielded Delhi University professor Manoj Jha, who is also the national spokesperson of the RJD.
Smart is prepared to play through the injury, though if it is determined he suffered a complete tear instead of a partial one, his season likely is finished, with surgery the primary option. "It's like a sprain right now".
Theis and Smart were both hurt in Sunday's game, with Smart's injury occurring when he dove to the floor. Smart scored 20 points with eight assists, seven rebounds and four steals against the Pacers on Sunday (Monday, PHL time).
Though he proceeded to play impressive basketball the rest of the game, the Celtics now fear he could need surgery that would keep him off the court for the rest of the season.
Al Horford, who missed the IN game because of an illness, was listed as questionable.