The 76ers were looking to stave off elimination on Thursday night in Game 6 against the Heat, but their challenge became a lot harder when they lost Danny Green to a left knee injury in the first quarter.

Green has been an integral part of Doc Rivers' rotation, bringing some defensive nous along with his long-range shooting. He has benefited from the return of Joel Embiid, who has drawn the attention of Miami's defense and freed up space for Green on the perimeter.

What is Green's injury, and when will he be available to play again? Here's everything we know about his status.

What is Danny Green's injury? The knee injury occurred early in the first quarter of Game 6 when Embiid tumbled into Green's knee, which bent in an unnatural manner as he absorbed the contact.

Green tried to get up, then collapsed to the floor in clear pain. He had to be carried to the locker room. The 76ers later announced that Green would not return.

Green has started in all 12 of the Sixers' postseason games so far, averaging 9.1 points and 3.4 rebounds in 28.7 minutes while shooting 40 percent from 3-point range.

How long will Danny Green be out? The 76ers are still waiting on the results of an MRI exam on Green's leg, but according to Adrian Wojnarowski of ESPN, there is "significant concern on the severity of the left knee injury."

As of Thursday night, the Sixers had not shared a timetable on a return.

Green is almost 35 years old and will be on a non-guaranteed contract following the conclusion of this season.