Gordon Hayward had to be deeply disappointed, but he hid it as best he could in a video message for his Boston Celtics teammates, who were going to be playing in their home opener while he had surgery for the gruesome leg injury he suffered in the season opener Tuesday night.

Hayward, wearing a hospital gown and speaking from his bed, said in the brief clip shown before tipoff Wednesday night against Milwaukee that he wanted “nothing more than just to be with my teammates and walk out on that floor.”

“What’s up, everybody? I just wanted to say thank you to everyone who’s had me in their thoughts and prayers,” Hayward said. “I’m going to be all right. [It’s] hurting me that I can’t be there for the home opener; I want nothing more than to be with my teammates and walk out on that floor tonight. I’ll be supporting you guys from here. Wishing you the best of luck. Kill it tonight. Thanks, guys.”

The Celtics lost to the Bucks, 108-100.

Hayward,  who signed a four-year, $127 million contract with the Celtics after spending his first seven seasons in Utah, isn’t likely to walk out onto that floor anytime soon — perhaps not until next season, according to his agent. “We expect him to make a full recovery and return to his All-Star form,” Mark Bartelstein told ESPN.

This season ended before it hardly begun for the 27-year-old. Barely into the first quarter, he jumped to try for an alley-oop pass, collided with LeBron James and landed badly, dislocating his ankle and fracturing his tibia with a loud sound that was heard in the arena and picked up by cameras. The injury shocked and horrified his teammates and the Cavs as they watched him being taken from Cleveland’s Quicken Loans Arena on a stretcher.

He found sympathy from another Boston athlete who has had his share of season-ending injuries. New England Patriots tight end Rob Gronkowski, who had a season-ending back injury that required surgery last season, advised Hayward to “go into rehab just like you go into anything else. Dominate it.”

Not that it’s all that simple.

“There is a big mental challenge, definitely, with that,” Gronkowski said. “It’s not just not being able to be with your teammates and all that. It’s outside of football, too. Because it takes away your whole life, going out like that . . . You can’t do anything. You can’t walk. You gotta have people do [things for you]. You get really frustrated. You just want the people around you to help you out and keep you in the best mind-set throughout the whole process.”

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