Gordon Hayward says that he is expecting to be ready to go for the start of the Celtics' season. (0:26)

BOSTON -- Eleven months removed from his gruesome opening-night ankle injury, Boston Celtics forward Gordon Hayward said Thursday that he's essentially at full health and has been playing 5-on-5 games with teammates in advance of training camp later this month.

Hayward even slipped into his No. 20 uniform after Thursday's news conference, one in which he repeatedly stressed how excited he is about the chance to finally get back on the court with teammates this season.

Gordon Hayward putting on the No. 20 jersey again ... pic.twitter.com/XBHbIo43Lz — Chris Forsberg (@ESPNForsberg) September 13, 2018

"I would say I'm basically 100 percent," Hayward said at the Auerbach Center, Boston's sparkling new training facility. "There's certain things that I think are going to take time -- even if I was 100 percent healthy, I'm not 100 percent as far as basketball-wise, just because I haven't played in a year.

"I'm trying to figure those things out. The last step for me as far as from a physical standpoint is a little explosion, that little last juice bounce that you get. So that's going to take me the longest time. But like I said, for the most part, I feel very good."

Hayward fractured his left ankle while landing awkwardly on an alley-oop attempt just five minutes into Boston's season opener in Cleveland last October. Hayward worked hard in hopes of a return last season but needed a follow-up surgery in late May to remove the plate and screws that were implanted in his fibula during the original surgery.

Throughout the summer, Hayward offered small glimpses of his progress via social media, including a snippet of him dunking off a drive in one-on-one work in mid-August. But Thursday was the first time he confirmed he had launched back into 5-on-5 work.

"It's so much fun being able to play again, and play with my teammates," said Hayward. "Using these past two weeks, and the next month or so, will be good to kind of get back into the game, feel the rhythm, the timing, different things like that. But it feels pretty good."

Hayward admitted that rehabbing from the injury was "the most difficult thing I've done." He detailed the mental challenges, including some dark days after the injury occurred, and then when he needed the follow-up surgery in May. But he gushed with energy about emerging from those tough times.

"I think when you go through a process like this, you just find out that, if you want to get back to the player that you were, it takes a lot of effort," said Hayward. "I think you find the fight within yourself because there's so many days where I wake up and it's like, 'Man, here we go again.' Another day I'm driving in, it's freezing cold weather here in Boston, below zero, going into the facility, and the team's in L.A., or they're in Miami or whatever, and they're playing, and I'm picking up marbles and putting them into a bucket. I'm standing on one leg and doing balance drills. I'm shooting from a chair.

"Like, all that stuff, to be able to get up and do it every day, and do it a little bit better the next day, and slowly work off getting out of the chair, and getting out of the boot, and now I can stand and shoot, and now I can do one dribble and shoot -- and just the long process. I mean, it was a process and a journey. I'm still not there yet, but it just helped me find kind of a fight in me."

One thing Hayward doesn't plan to do is watch video of the injury.

"I haven't watched it. Scrolling through Instagram -- you know how today's social media works -- I've seen it on my search feed a little bit, but I haven't watched the video," said Hayward. "I don't plan on watching the video. I'm moving forward -- and past it."

Hayward said he plans to be on the court during Boston's four-game preseason slate and was adamant he'd be full-go for opening night.

"Yeah, 100 percent I expect to be out there [on opening night]," said Hayward. "This is what this time is for me -- to kind of find my groove a little bit. Like I said, you can do all the drills you want, all the cardio, the jumping [and] agility stuff. But there's nothing like playing 5-on-5, so when I play out here with my teammates, when we get into practice situations, that's going to be the best -- playing in the preseason games, that will be the best work I can get."

Hayward also said that he thinks this year's team is capable of big things.

"Watching the guys last year just gave me a lot of confidence in our team and what I think we have the ability to do," said Hayward. "I've been playing with some of them these last two weeks, and we have a lot of talent on this team. We have a lot of depth, and it's going to be a fun year."