The Baltimore Ravens have partnered with a tech company to practice against holographic players.

“Right now, what you are seeing is a holographic football team coming at you and getting into their formation,” says Jim Pietila, CEO of Mixed River.

Founded late last year, Mixed River offers not virtual reality but “mixed reality,” which means the real world intersects with images or data.

Virtual reality also could help reduce head trauma injuries, which are under increasing scrutiny by former players and the league.

“One of the attractions to the technology is the ability to get those mental reps that don’t involve contact,” said Damani Leech, the NFL’s vice president for football strategy and business development. “I think you see it with other technology — with the robotic tackling dummies to allow you to improve your tackling form without hitting another person.”