Boston Celtic’s forward, Gordon Hayward, was quickly taken off the court after a serious-looking leg injury, in their game against the Cleveland Cavaliers on Tuesday night.

During the Cleveland Cavaliers vs. Boston Celtics game in the Quicken Loans Arena, Gordon Hayward dropped to the floor after an unexpected collision [VIDEO] with LeBron James. The player was aiming for an alley-oop pass but ended up injuring his leg in the first quarter.

Slow motion clip revealed NBA accident

In a slow-mo clip of the incident, Hayward’s leg was in the wrong position when he fell. Everyone was alerted when he started wincing painfully.

The players and the audience quickly understood the nature of his injury, when security immediately covered him and the team’s staff tended to him. The game was on pause at 12-9, Celtics in the lead. “Oh my gosh. And that is how quickly a season can change,” the season’s commentator said.

The tide of the whole game changed, especially for the Celtics. The team huddled together, followed by the fans giving a standing ovation as Hayward left the court. By the end of the game, Cavaliers took the win at 102-99.

Brad Stevens confirms that Gordon Hayward is fractured

Boston’s coach, Brad Stevens, announced that Hayward fractured his tibia and dislocated his left ankle. “He's put in a lot of great work. And I thought he had his most comfortable week as far as feeling like he was going to play really well.

But now we’ll hopefully get a full recovery, right? And so it's a tough deal, but I guess that's part of it, the risk of injury. I really feel for him.”

Aside from the Celtic’s shock over what happened, players on the other team were struck about the whole situation as well. Jeff Greene, who was on the Cav’s bench during the first quarter, saw everything happen in a matter of seconds. “I was hoping I didn’t see what I saw, it was gruesome,” he said, “I thought it was his lower back or his buttocks or something. You never wish injury on anyone, especially such a good player like that.”

Everyone in the room was shocked and saddened by the mishap. The camera did not miss Dwyane Wade, Lebron James, and Isaiah Thomas’ reactions either.

The Cleveland Cavaliers will continue on with their next game, while Gordon Hayward will have his surgery at New England Baptist Hospital. Boston Celtics will face the Milwaukee Bucks on Wednesday night. The loss of a teammate is expected to be hard to work around.