The last thing the Celtics needed was another injury to a player who is already filling in for an injured starter. Tony Allen said he hyperextended his left shoulder when he collided with Marcus Banks, who was setting a screen as Allen was going for a steal on Hedo Turkoglu late in the fourth quarter of Boston’s win over Toronto at TD Garden on Saturday night.

“It hyperextended when I tried to get the steal and Marcus Banks came in with the screen,” Allen said. “I don’t think he meant anything bad by it.”

Allen, who started in place of Rajon Rondo, said he will come in and get stimulation treatment on the shoulder on Sunday and should be ready to go for practice on Monday in Waltham.