Concussion, starring Will Smith, has elicited emotional reactions from current and former NFL players.

The film, based on true events and released on Christmas day, chronicles the work of Dr. Bennet Omalu (Smith), a forensic pathologist who has been vocal against the NFL’s attempts to suppress his research on the discovery of chronic traumatic encephalopathy (CTE) and brain damage in deceased football players.

The MMQB screened Concussion with 70 former NFL players, and received emotional reactions both for and against the film from several players on Twitter.

Took my boys to #Concussion last night, important movie 4 all those involved in game! As we know more we MUST do more… #CommunicationIsKey

— Kurt Warner (@kurt13warner) December 26, 2015

At The Movie "CONCUSSION "words can't describe the range of Emotions!!!

— Bernie Kosar (@BernieKosarQB) December 26, 2015

Just watched Concussion. A great movie & a frightening reality.

— Matt Overton (@MattOverton_LS) December 25, 2015

Concussion was a great movie!

— Jaiquawn Jarrett (@jaiquawnjarrett) December 25, 2015

Just saw concussion. Scared the hell out of me.

— Dustin Fox (@DustinFox37) December 26, 2015

Watching this movie concussion and sheeesh!!!

— Johnthan Banks (@JBanks_27) December 26, 2015

According to Sport Illustrated, NFL players are able to redeem free admission to the movie by showing their NFL Players Association card at Cinemark theaters.

The film is not necessarily putting the football industry in a happy place.

“I probably won’t be getting my free Super Bowl tickets this year,” Will Smith told CNN about the reaction he expects from the NFL.

Film Review: Football Takes a Hit in Will Smith-Led 'Concussion' https://t.co/t7e2Oyf5iA pic.twitter.com/ZNq5WQ6C3V

— Hollywood Reporter (@THR) December 27, 2015

In the months leading up to the release of Concussion, leaked Sony emails indicated that its filmmakers were concerned about upsetting the NFL.

“We welcome any conversation about player health and safety,” said the NFL in a statement sent to CNN. “Broader and deeper awareness of these issues will positively impact all athletes.

“The NFL has made numerous changes to the game to enhance the health and safety of players at all levels of football. These include nearly 40 rule changes in the last decade, strict concussion protocols, and better training and sideline medical care.

“We’re seeing measurable results, including a 34% decrease in concussions in NFL games since the 2012 season.

“Additionally, we are funding independent scientific and medical research and the development of better protective equipment to advance further progress. The game continues to change, and the safety of our players remains our highest priority.”

This man is the real-life inspiration for Will Smith's "Concussion," out today https://t.co/AjlKQyEP14 pic.twitter.com/Ub4Cq6tGwX

— Forbes (@Forbes) December 25, 2015

Although Smith is an avid football fan and has a son who plays, the 47-year-old actor hesitated on whether to make the film. In the end, he says it was important to bring the doctor’s story to the attention of the world and to honor those who have suffered as a result of football-related brain injury.

“The production was extremely heavy,” Smith said. “You know, it’s not just a movie. It’s people’s lives that we’re trying to do justice to their suffering.”