There did not appear to be any contact on the play, which occurred midway through the third quarter. Chalmers was unable to put any weight on his right leg and needed help to leave the court. Chalmers will have an MRI on the foot in Memphis on Thursday, the team announced during the Grizzlies' 116-96 loss.
Coach Dave Joerger said afterward he had no update on Chalmers, who left the locker room in a wheelchair with a boot on his right foot.
"When Mario went down, that was a tough deal for us," Joerger said. "Our guys played their tails off. But that team right there ... they got cooking, and they were tough for us to catch."
Chalmers had 11 points, five rebounds and five assists in 22 minutes before leaving the court. He had averaged 10.8 points and 3.8 assists for Memphis, mostly as a backup for Mike Conley. Conley has missed the past two games with a sore left foot.
Grizzlies forward Matt Barnes referenced the Gasol, Conley and Randolph injuries in his reaction to Chalmers'.
"When it rains it pours. To lose this many guys to injury, back to back to back, once we finally started to get a rhythm with our new guys, it's a crazy situation."
Tony Allen noted how much difficulty Memphis' offense had playing without a true point guard.
"Obviously, to see another fallen soldier go down due to injury, it deflates you, takes a lot out of you ... We tried to play together, but obviously you could see his work on the court. We didn't have a poised point guard today. Guys were missing out on Coach's sets that he was trying to run."
Information from ESPN's Kevin Arnovitz, Celtics reporter Chris Forsberg and The Associated Press was used in this report.