The huge fan-favorite received a hard, high hit along the boards from Stars' winger James Neal early in the first period after playing the puck into the offensive zone.
Prucha, who was traded to Phoenix at the trade deadline last season, was motionless on the ice for about seven minutes before being wheeled off.
There was no penalty on the play, but this type of hit has been one of the huge hot-buttons in the NHL of late.
"All I've heard for months is how we're bearing down on head shots," Coyotes' coach Dave Tippett said. "Well, that's a clear head shot...it's a hit to the head, and you have a guy that's basically knocked out cold."
Tippett was "baffled" by the referee's non-call on the play.
Upon watching the video, I don't think it was as clear-cut as Tippett feels it was, but, he needed to say that to stick up for his player.
Prucha was released from the hospital after evaluation and is day-to-day.
The Czech is no stranger to hard, bone-crunching hits. During his time in New York, that was one of his biggest draws for fans. Prucha's ability to bounce back after taking what seemed to be countless, gigantic checks was extremely admirable, especially for someone his size.
Petr Prucha scored 30 goals his rookie season for the Rangers, the first Ranger to do so since Tony Amonte scored 35 during his rookie season in 1992.
Prucha has 11 goals and nine assists in 62 games this season.