The center played seven games for the United States at the 2019 IIHF World Under-18 Championship in April and seven games at the 2019 IIHF World Championship in May. The United States was eliminated in the quarterfinals of the World Championship on May 23 and Hughes arrived in Buffalo four days later.
"I think I knew coming into the combine I wasn't going to do the testing because I really haven't trained for it, playing hockey the past two months," Hughes said. "I really haven't had a break. It just didn't make sense to do the testing. My body needed a bit of a break.
"That said, I'm a competitive kid and I felt like I could have done well in some of this stuff."
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A specific injury was not disclosed. The tests include a standing long jump, vertical jumps, pull-ups, bench press, grip strength, shuttle run, and stationary bicycles. Body-fat percentage and wingspan are measured.
Hughes led the USA Hockey National Team Development Program Under-18 team with 112 points (34 goals, 78 assists) in 50 games this season. He holds NTDP career records for assists (154) and points (228) in 110 games over two seasons.
He was one of 17 players from the National Team Development Program invited to the combine and was interviewed by 10 NHL teams this week, including the New Jersey Devils, who hold the No. 1 pick in the 2019 draft after winning the NHL Draft Lottery. The New York Rangers have the No. 2 pick and Chicago Blackhawks have the No. 3 pick.
"The interviews are tough because you have to refocus every time," Hughes said. "Obviously, the Devils and the Rangers were the most important interviews for me. I felt like both of those went good and I was comfortable with both of them."