(WTVO) — Monday night’s NFL game between the Buffalo Bills and Cincinnati Bengals had a scary moment when Damar Hamlin collapsed on the field after making a tackle.

Reports have come out that cardiac arrest caused him to fall, which opens many questions about what happened. Many factors were at play, and doctors suspect that commotio cordis was the reason.

They said that first responders are critical in these cases.

“Hamlin appeared to make a routine tackle on Bengals wide receiver Tee Higgins, but then collapsed just second later,” said Jake Karalexis, a multi-media journalist for Fox.

Reports have confirmed that cardiac arrest resulted in Hamlin losing consciousness in Monday night’s football game. Many doctors speculate that it was commotio cordis, but the question is how did a healthy 24-year-old suffer from this?

Three things need to happen.

“One, the location has to be very specific,” said Dr. Sudhir Mungee, director of OSF Healthcare’s structural heart program “It’s almost like in the center of the left side of the pericardium.”

The second is the power of impact, which is why the risk can be more common in sports like baseball, when players get hit with the ball, or contact sports in general.

The third reason is what makes Hamlin’s instance so rare.

“It’s sixty beats per minute, and in that one second of heart cycle, there’s only about 10-30 milliseconds of time that if the impact was to happen during that time of the cardiac cycle, the heart can go into a very abnormal, lethal, electrical rhythm,” Mungee said.

This is so called ventricular fibrillation. While it is very rare, it can be more common in younger people who do not have the built-up mass around their chest.

Doctors said that they cannot stress enough about first responders’ importance in this case, as they try to get blood flowing back to the brain cells.

“What you saw on the football field last night was an example of a team working really well,” said Jeff Pothold, chief quality officer and emergency medicine/medical physician at UW Health. “After the event happened there wasn’t a whole lot of what’s going, what’s happening. Those medical crews sprang into action. They had quickly assessed that the induvial was in cardiac arrest and started life sustaining measures, including cardiopulmonary resuscitation, also known as CPR.”

The timetable for Hamlin is unknown. Doctors are seeing how his vital organs are reacting and will go from there. They also said that this is an extremely rare case and that parents should not feel any different about their children in sports then they already were without knowing all the other details.