Buffalo Bills player Damar Hamlin is opening up about his sudden collapse during a football game and his remarkable recovery.
During an interview with Michael Strahan on "Good Morning America," the 24-year-old Bills safety said he feels grateful to be alive.
"That just kinda put things in perspective for me, you know, hearing it from the doctor," Hamlin said. "Things could have went differently and the details of the situation of everything that happened on the field -- it could have been -- it could have been the last of me."
Watch the Michael Strahan interview with Damar Hamlin on Monday at 7 a.m. ET on "Good Morning America."
Hamlin said he remembers preparing for that Monday night game six weeks ago against the Cincinnati Bengals, one of the last of the NFL season. He said he was feeling great.
"I remember the things that we were focused on going into the game," Hamlin told Strahan. "Just trying to get a win."
But with 5:58 left to go in the 1st quarter -- after making a tackle -- Hamlin stood up and then suddenly collapsed, going into cardiac arrest.
Denny Kellington, the assistant athletic trainer for the Bills, immediately began performing cardiopulmonary resuscitation, or CPR, on Hamlin.
If CPR is performed on a patient immediately, it can double or triple the odds of survival, according to the American Heart Association.
Emergency personnel also used automated external defibrillator, or an AED, a medical device that analyzes the heart's rhythm and will deliver an electrical shock if needed.
Strahan noted that Kellington is the one who alerted everyone on the sidelines that Hamlin's medical condition was serious.
"I owe Denny my life," Hamlin said. "Literally. He loves to say he was just doing his job, which is true, you know? And that night, he was literally the savior of my life."
He added, "I'm truly thankful for and I don't take for granted."
Hamlin was taken to the University of Cincinnati Medical Center and remained in critical condition in the intensive care unit for several days -- three of which were spent on a ventilator.
However, day by day, his condition improved and four days after his cardiac arrest episode, he woke up and was able to communicate with family and teammates.
Hamlin said he remembers waking up and seeing his parents and friends, who were having conversations around him. But he mostly remembers the first question he asked via writing: "Did we win?"
Doctors replied, "Yes. You won the game of life," he said.
'When I saw that, I said, 'Okay. He's an athlete. He's committed,'" Strahan said. "Cause you wake up and you're sittin' and you're going, 'Did we win?' Your mind is still on the game."
Hamlin replied, "I'm competitive, playing with my full heart and everything I've got in me. That competitive nature in me was just still just thinking about the game."
One week after his medical episode, Hamlin was discharged from UC Medical Center and transferred to Buffalo General Medical Center in western New York.
Doctors have described his recovery as "remarkable" and it didn't take him long to start walking again, eating regular food and starting physical therapy.
Hamlin declined to discuss what doctors believe may have caused his heart to stop beating, adding that tests are still ongoing. But he said he feels lucky to be alive.
"I'm just thankful [God] gave me a second chance, you know, just to live normally and just come out almost without a scratch on me," Hamlin said. "Just to be able to keep going."
Physically, Hamlin said he is doing well and hopes to get back to playing football eventually, but he told Strahan that his emotional recovery will take longer.
"I'm still working through things," he said. "I'm still trying to process all the emotions and the trauma that comes from, you know, dealing with a situation like that and not really having people around or, you know, like, no one in my immediate circle who's dealt with something like that."
Hamlin said he's teaming up with the American Heart Association with a goal of getting 3 million people to sign up and learn how to perform CPR.
Tune in on Monday at 7 a.m. ET on "Good Morning America" to see what Hamlin said about his recovery and what's ahead, including his future in professional football.