GLENDALE, Ariz. — Jakob Chychrun was running sprints this summer on the same hill behind the same rink in Arnprior, Ontario where he has trained for years.

“The group I train with, at the end of the workout, we’ll do that for cardio,” Chychrun said. “We’ll do 10 hill sprints timed. We’ll go down backwards because it’s easier to brace yourself and rest for the next set because once you get down you’re going right away again.

“It’s easier on the legs.”

This time it wasn’t.

“I just stepped in a little pothole and my leg just extended and I felt it pop right away,” he said. “It was unfortunate. I’ve been doing the same exact thing on the same exact hill for a while; just one unlucky step.”

When Chychrun received the diagnosis — one that neither he nor the Coyotes wish to divulge — his first call was to his mom. His second was to Coyotes general manager John Chayka.

“Obviously, it was just tough to get that news,” Chychrun said. “I think John helped with that. He said. ‘look, we can sit here and dwell on it or we can move forward with it.’ I was in Vail the next day for surgery.”

Knee specialist Robert LaPrade performed the surgery at The Steadman Clinic in Vail, Colorado on Aug. 3. In less than a week, and on the recommendation of Coyotes trainer Dave Zenobi, Chychrun was headed to Philadelphia to rehab with Bill Knowles, the director of reconditioning and athletic development at HPSports in Wayne, Pennsylvania.

Chychrun was determined to beat the timeline for a return that his doctors had set for him.

“At first, they told me no less than six months. Then it was definitely not before the New Year,” Chychrun said. “I honestly didn’t listen to that. I understand people have to be conservative with that and I also understand there’s a way to do it more progressively and aggressively. That’s the way we went.”

Chychrun’s parents, Nancy and Jeff, flew up from Boca Raton, Florida to be with him for the first week or so while he was still struggling to get around.

“I’ve seen a lot of injuries,” said Jeff Chychrun, who played for four NHL teams from 1986-94. “I’m finding there’s a lot of emotions that a parent goes through that are different from playing. It was so unfortunate because it really was a simple thing at the end of a workout.

“He was upset for about half an hour after he got the news that he was going to have surgery but that was it. He said, ‘we’ll get it fixed and get back.’ He really just focused on what he had to accomplish.”

Knowles kept Chychrun’s muscles from atrophying, and he maintained Chychrun’s range of motion and flexibility by putting Chychrun in a pool immediately.

“The pool cuts your weight about in half and the flotation vest cuts it in half again so when you’re in, there’s no loading through the knees,” he said. “You can walk in the pool when it’s shoulder high or chest high and move freely. It’s unbelievable. You just had surgery and you get in the pool and feel normal.”

Once Chychrun’s parents returned home, he was on his own, rehabbing twice a day, napping in between, eating dinner and going to bed.

“It was the same thing every day,” he said. “It was pretty consistent and I like that. I wasn’t there to do anything other than that.”

Chychrun experienced pain from time to time, but Knowles assured him that it was normal and had nothing to do with the surgery.

“There are things you can work through and things you can’t and he was really confident with everything we would do and everything I was feeling,” Chychrun said. “Having support like that reassured me and made me push even harder because I knew it was OK.”

Chychrun said Knowles’ unconventional approach shortened the timeline.

“He’s open to different ideas that are not in the mainstream,” Chychrun said. “There are so many modern training techniques and rehab techniques he’s in tune with. If I didn’t take that process, I don’t think I’d be playing right now.”

When Chychrun finally started skating on Oct. 21, he started pushing his GM and coach Rick Tocchet for a return to the ice.

“I knew they were going to say ‘no,'” Chychrun said, smiling, “but I had to let them know I was ready.”

Chychrun completed his remarkable comeback by scoring in his debut in Vegas on Sunday. He also scored in his first game back from a shoulder injury that sidelined him for eight weeks in his first season with Sarnia of the Ontario Hockey League in 2014-15. It’s the same thing he did after missing a month when he was 13 and playing for the Little Caesars.

“He’s just a physical freak, but it’s a testament to Jakob’s work ethic that he was able to come back so fast,” Chayka said.

While Chychrun insists he never got depressed or frustrated during the rehab process, getting back on the ice allowed him a chance to briefly exhale.

“It’s like a weight off your shoulders because you watch for so long and you’re out for so long,” he said “You don’t want to do anything wrong and have any setbacks. When you go through all the steps and process correctly, it’s very rewarding when you can come back ahead of schedule just because of all the time I put into it.”

Coyotes at Bruins

When: 5 p.m., Thursday

Where: TD Garden, Boston

TV: FOX Sports Arizona

Radio: ESPN 620 AM

Records: Coyotes — 7-18-5. Bruins — 12-9-4.

Injury report: Coyotes — D Niklas Hjalmarsson (upper body) is day to day. Bruins — F Peter Cehlarik (lower body) is out indefinitely. D Adam McQuaid (broken fibula) is due back in mid-December. F Jake DeBrusk (upper body) is day to day and could play.

Bruins scouting report: The Bruins are 6-2 in their last eight games … F David Pastrnak leads the team with 14 goals and 24 points … The Bruins have defeated the Coyotes 11 straight times; Arizona hasn’t defeated Boston since Oct. 9, 2010 in Prague, Czech Republic. TD Garden has been the Coyotes’ recent house of horrors. They have lost their last four games there by a combined score of 16-3.

Coyotes scouting report: The Coyotes recalled defenseman Kyle Capobianco from Tucson of the AHL on Monday and he is expected to make his debut in Boston … Scott Wedgewood will start in goal with Antti Raanta serving as the backup.

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