"I wish I could've made it happen sooner,'' says Gillies now, "so (Horton) could've seen it in person.
"I guess it was the next best thing. I'm sure he was watching.
"Having the people - parents, family - who sacrificed so much for me thought the years … that's what made it special."
That would be - and is - his only NHL appearance to date.
Fast forward to today, summer 2017, a month away from the start of training camp. The 23-year-old Gillies is outside Indianapolis, Ind., his girlfriend's home, spending the off-season working with his USHL goalie coach, Jamie Morris.
In the interim, April 6th to now, the organizational blue paint hasn't gotten any less crowded. NHL-tested Mike Smith and Eddie Lack have come aboard to start as the Flames' 1-2 punch. After a solid year, Gillies' Stockton sidekick David Rittich is looking to make inroads (Both Gillies and Rittich signed one-year, two-way deals this off-season).
And there's young 'un Tyler Parsons to consider, lurking out there on the horizon.
"Obviously, Ritter and I have a great relationship,'' says Gillies. "Then Eddie Lack and Mike Smith are very experienced, from all I've heard great people, and great goalies.
"This year, I feel I'm closer. I feel I'm ready to make that 'next step' everybody talks about. But you've still got to prove it.
"There's just a different feeling from a personal standpoint. (In 2016) I'd just come off a year of missed hockey. As much as I kept telling myself being hurt wouldn't affect me, it did for a while.
"I mean, it happened to Carey Price, the best goalie in the world.
"And then the Flames were healthy throughout the entire roster pretty much all year so the opportunities were few and far between.
"I'm thankful I got the one.
"I thought I played well. Thought I played my game. And we had a great team performance.
"I'm looking to build off that. It was kind of stepping stone to me solidifying in my own mind: 'OK, I can do this. I can play in this league.'
"I'm just focus on getting better. It's been a good summer."