Sanheim, the No. 17 pick in the 2014 NHL Draft, was an offensive force during his final two seasons with Calgary of the Western Hockey League, with 133 points (30 goals, 103 assists) in 119 games from 2014-16. But that offense-first style wasn't going to work last season, his first with Lehigh Valley of the American Hockey League, and it made for some growing pains.

Philadelphia Flyers defenseman prospect Travis Sanheim spent last season learning the differences between junior hockey and the pros, and that experience could serve him well in his quest to reach the NHL.

"At the junior level I was able to do a lot of stuff I wasn't able to do at the pro level," Sanheim, 21, said. "Jumping up in the play and getting caught around the net or getting too low. In junior I was able to get back and cover myself up lot more easily. [In the AHL] you make mistakes and you get caught somewhere, you know it's going to end up in the back of your net. Learned some valuable lessons in the first few weeks and went over a lot of video with the coaching staff. They were great to me."

Sanheim said he spent lots of time working on and off the ice with Lehigh Valley coach Scott Gordon and assistant Kerry Huffman.

"They knew coming from junior there would be lessons to be had," Sanheim said. "They gave me the opportunities going forward and I took advantage of them throughout the season."

After he had eight assists and a plus-4 rating in his first 18 games for Lehigh Valley, Sanheim had 29 points (10 goals, 19 assists) and a plus-3 rating in his final 58 games.

"It wasn't a slow start, but he needed a little more structure in his game," Flyers general manager Ron Hextall said. "He was a little bit all over the map, which is what he was in Calgary because they didn't have a real high-scoring team so he was up the ice a lot. … So it took him about a month, month and a half for him to kind of learn situations and when to go and when not to go. But he had a real good second half of the year and came a long way."

Sanheim said he could see the improvements as the season went on.

"When you're watching video from the first half of the season or first month, month and a half of the season and you see some of the stuff I'm doing, and then [you see] what you're doing weeks later, and you can see the improvement," he said. "To me, I was finally getting it and I needed to keep building on it."

Sanheim also has gotten stronger. He was 6-foot-3, 181 pounds when the Flyers drafted him, but said during development camp last week he's up to 205 pounds. More than weight, however, he feels stronger on the ice.

"Playing my first pro season, I felt comfortable going against anyone on the other side," he said. "Still want to continue to get stronger, as do a lot of people. I think I've definitely put on a lot of weight, a lot of strength throughout the time I've been with the Flyers. I want to continue to keep doing it."

Flyers coach Dave Hakstol said he was impressed by what he saw of Sanheim during development camp.

"Just the assertiveness he handles himself with in every phase," Hakstol said. "I will reference both on and off the ice and that is just maturity, how a young man grows and develops. I think if I was going to use one word to show the growth of Travis [it] is assertiveness."

The Flyers have openings on defense this season, but the competition will be tight. Samuel Morin and Robert Hagg, teammates with Sanheim at Lehigh Valley last season, impressed in one-game NHL call-ups, and Philippe Myers, a promising prospect who was one of the final cuts in training camp last season, will turn pro this season.

Sanheim said the growth he showed last season led to more responsibilities with Lehigh Valley, including time on the penalty kill, and will help him in his quest to make the Flyers this season.

"I think just being relied upon down with [Lehigh Valley] toward the end of the season and the playoffs, playing a regular role with the team, just makes me that much more confident going into [training] camp," he said. "Knowing I can play at that level down there, hopefully that will translate to camp."