BUFFALO – In the opening minutes of a goalie’s NHL debut, facing a shot or two and simply feeling the puck can help him calm any nerves and settle into the game.

So as Sabres goalie Colten Ellis waited and waited for his first chance to make a save on Wednesday, it was fair to wonder how he would react.

Well, Ellis, a recent waiver claim who backed up veteran Alex Lyon in the Sabres’ first six games, responded when the Detroit Red Wings finally challenged him in KeyBank Center.

Ellis, 25, stopped the first shot Detroit pumped on him 6:59 into the contest, a 27-foot wrister from old friend Jacob Bernard-Docker, and looked sharp throughout the Sabres’ 4-2 victory that ended Detroit’s five-game win streak.

The rookie was perhaps Sabres’ biggest difference-maker, making some critical, momentum-swinging stops in a tight game.

“The boys came out strong, and they were playing so good, and I was kind of like, ‘Gee, I need a shot here at some point to get me into it a little bit,’” Ellis said following his splendid 27-save effort. “But I can’t commend them enough for all the effort tonight.”

Ellis stymied Marco Kasper’s breakaway late in the first period to keep the game tied at 0 and Dylan Larkin’s breakaway out of the penalty box early in the second to keep the Sabres down just 1-0.

“Got a little concerned because (he faced) no shots for the longest period of time,” said coach Lindy Ruff, whose Sabres have won three of their last four games. “One of the first big chances he faces is a breakaway and makes a heck of a save, and I think that alone probably made him feel good.”

Winger Jason Zucker tied the game at 11:37, converting a nifty pass from linemate Jack Quinn. Forward Tyson Kozak gave the Sabres their first lead at 16:28.

After Quinn’s power-play goal 4:15 into the third period put the Sabres up 3-2, Ellis slid across the crease and stopped Alex DeBrincat’s point-blank shot on his doorstep about five minutes later.

At 8:10, winger Josh Doan scored, giving the Sabres a two-goal cushion.

“Those are the type of saves of you build off of,” Ruff said. “You get a big save, and then a lot of times you go down the other way and score. Bench was fired up. The crowd was fired up when you see a save like that. So it was a big momentum swing in the game.”

Ellis said “you fuel on moments like that in the game.”

After the Sabres added Ellis, Ruff said the newcomer would play. Then Lyon thrived with his heavy workload as No. 1 goalie Ukko-Pekka Luukkonen recovered from his lower-body injury.

It seemed like Lyon, who spent the last two seasons with Detroit, might face his old team. But the Sabres decided he needed a rest.

“Just too many games for Lyon,” Ruff said of why Ellis started Wednesday. “Really, we just felt we reached a point. No more than that. Nothing to do with him and Detroit or anything. Really, it got to a point where we just felt we’ve got a busy week, and we have to get him in.”

For Ellis, who toiled in the St. Louis Blues’ system for four years, spending most of his his time in the ECHL, Wednesday was a magical day.

The Whycocomagh, Nova Scotia, native said he had 25 to 30 supporters in the crowd of 15,104 fans.

“I was pretty emotional before the game,” he said. “Me and my fiancée were sitting in the hotel and found some old pictures of me playing hockey. Kind of didn’t really expect that for myself.

“Just, obviously, ecstatic to have all my family here and so many supporters here. It’s so special to get to share this moment with them.”

TNT cameras showed his mother nervously watching him throughout the night.

“She’s usually a wreck,” Ellis said. “She got through it, so good for her, but she definitely gets picked on for that.”

The Sabres finished the game down a forward after Zucker left late in the second period with an upper-body injury. Ruff said he was being evaluated and did not have an update.

Quinn assisted on the first two goals and had a three-point night.