Three summers ago, the Blackhawks invited six goaltenders to development camp.

One of them was Collin Delia. Then a rising senior at Merrimack College, Delia attracted the Hawks’ attention, earned another invite to the 2017 camp and signed an entry-level contract.

That’s a path that the Hawks’ four goalie invitees — Devin Cooley (University of Denver), Zackarias Skog (American International College), Stefanos Lekkas (University of Vermont) and Mareks Mitens (Lake Superior State) — in 2019 are eyeing tantalizingly.

“For sure, the end goal is an NHL contract,” Cooley said Wednesday. “But when you’re here, you’ve just got to take things one step at a time.”

There’s a substantial opportunity in goal with the Hawks. The team has only four goalies on NHL contracts: Delia, prospect Kevin Lankinen and veterans Corey Crawford and Robin Lehner, both of whom will be unrestricted free agents next July.

Rockford also has Matt Tompkins and Chase Marchand on AHL contracts, and the Hawks retain the rights to recent draft picks Alexis Gravel and Dominic Basse, the other two goalies in camp. Nonetheless, the organization has relatively little goaltending depth compared to other franchises.

“The message to these players is you’re here for a reason, because we think you’ve got skill and potential,” general manager Stan Bowman said. “We want to see how you perform this week and [see] how you take feedback, what’s your work ethic like? And then we’re going to follow them.”

The Hawks already have been following Skog. AIC coach Eric Lang and Hawks developmental goaltending coach Peter Aubry have been sending clips and feedback since midway through last season.

Skog’s .899 save percentage at AIC wasn’t great, but he was at .915 beginning in mid-January and stopped 33 of 34 shots in a huge postseason upset of top-seeded St. Cloud State.

“Me and Peter had a good talk during the year, and they liked us, so I got an invite,” the 24-year-old Swede said. “It’s always cool to see new faces and new facilities, and the Blackhawks’ organization is great.”

Cooley, 22, and Lekkas, 23, are coming off solid college seasons. Cooley’s .933 save percentage was the second-best in Denver’s history; Lekkas finished at .930 on a rebuilding Vermont squad.

Cooley, who also attended the Maple Leafs’ development camp in June, was noticed by Hawks scouts in town to watch Denver teammate Ian Mitchell. Now, Mitchell is serving as his de facto Hawks ambassador.

“I get to room with him and spend time with him, and he’s introduced me to a lot of the other staff and prospects,” he said.

Yet, the monstrous 6-4 goalie has done more than serve as Mitchell’s sidekick.

He has stood out as the best goalie at camp this week, even including draftees Gravel and Basse. He has looked nearly flawless, both in goalie-specific workouts and during mini-scrimmages. And his size is obviously a big plus, too.

Cooley could be the Hawks’ next Delia. But if not, perhaps Lekkas, Skog or Mitens will be.

“It’s not out of the realm that, a couple years from now, these guys could become Blackhawks,” Bowman said. “They’re not all going to fall into that category, but if they show well and they impress us.”