His first game as a Boston Celtic had a horrific ending.

Gordon Hayward, the prized free agent signed by Boston in the offseason, suffered a broken ankle midway through the first quarter of the team's season opener at Cleveland on Tuesday night in what is as inauspicious and grotesque an injury you will ever see.

You can see the video here, but be warned: it is graphic.

It's unclear how long Hayward will be out, but you'd have to think he's got a long road ahead of him. He's in the first year of a four-year, $128 million deal.

In what almost seems to be an afterthought, the Celtics squandered a big second half lead and dropped the game, 102-99.

The NBA community rushed to wish him the best on Twitter. Notable among the people who chimed in is Paul George, who is knows a thing or two about suffering a brutal injury during a game.