(CINCINNATI, Ohio) — Buffalo Bills safety Damar Hamlin is starting to wake up after collapsing from cardiac arrest during a game against the Cincinnati Bengals, physicians treating him at University of Cincinnati Medical Center said.

Hamlin has shown “substantial improvement” in the past 24 hours and it appears his neurological function is intact, UC Health’s Dr. William Knight IV and Dr. Timothy Pritts said during a press briefing Thursday.

When Hamlin first woke up last night, he asked, “Did we win?” according to the doctors, which they took as a good sign.

“So we know that it’s not only that the lights are on. We know that he’s home. And it appears that all the cylinders are firing within his brain, which is greatly gratifying for all of us,” Knight said.

Hamlin can’t speak yet, as he is still intubated, but is able to shake his head and write short notes on paper, they said. His family and the Bills staff have discussed with him what happened and the support he’s received, according to the doctors.

He continues to be critically ill and remains on a ventilator, but has good lung function, the doctors said. He is heading in the right direction, they said, and noted his age, fitness level and the quick care he received on the field during Monday night’s game as contributing to his improvement.

The Bills also said Hamlin is showing “remarkable improvement” after the incident.

“Per the physicians caring for Damar Hamlin at the University of Cincinnati Medical Center, Damar has shown remarkable improvement over the past 24 hours,” the team said in a statement on Twitter Thursday morning. “While still critically ill, he has demonstrated that he appears to be neurologically intact. His lung continue to heal and he is making steady progress.”

Hamlin’s teammate, fellow defensive back Kaiir Elam, also tweeted Thursday morning that Hamlin was “doing better, awake and showing more signs of improvement.”

Hamlin woke up “much sooner than expected,” Dr. Thom Mayer, an NFL Players’ Association medical official, told reporters on a Zoom call Thursday.

“All signs are highly optimistic and point to what is likely to be a full neurological recovery,” Mayer said, though cautioned that “there is a long way to go.”

‘Something that we’ll never forget’

Bills head coach Sean McDermott teared up talking about Hamlin and his recovery.

“Glory to God for his keeping Damar and his family in the palm of his hand over the last couple of days,” McDermott said during a press briefing Thursday.

Bills quarterback Josh Allen told reporters the scene on the field has been playing “over and over” in his head.

“It’s something that we’ll never forget, but to know that Damar is doing okay … we heard that news this morning and there’s nothing that could have been told to us to bring our day down,” he said.

“We’re extremely happy for him and his family,” he continued. “We just want to love up on him, so the next chance we get.”

Hamlin, 24, remains hospitalized in critical condition in the intensive care unit at University of Cincinnati Medical Center. The second-year safety from the University of Pittsburgh collapsed during the Monday Night Football game against the Bengals after making a tackle in the first quarter.

The game was halted and then suspended indefinitely after doctors provided CPR to resuscitate Hamlin on the field before taking him to the hospital. The NFL announced Thursday night that the Bills-Bengals game will not resume and has been canceled.

Doctors had told family members Wednesday morning that Hamlin’s condition was moving in a “positive direction,” according to Hamlin family spokesperson Jordon Rooney.

In an interview with ABC News, Rooney also clarified statements made by Hamlin’s uncle, Dorrian Glenn, who said Tuesday that Hamlin had to be resuscitated twice — on the field and at the hospital. Rooney said that was a misunderstanding and that Hamlin was not resuscitated more than once.

Responding to reports that the defibrillator used on Hamlin malfunctioned, Rooney said those reports were incorrect and that all of the medical equipment worked properly.

President Joe Biden told reporters on Wednesday that he spoke to Hamlin’s parents “at length,” though he did not elaborate on the conversation.

Hamlin’s family thanked the “dedicated first responders and healthcare professionals” at the hospital for their “exceptional care” in a statement released Tuesday.

Likely life-saving on-field response

Medical staff from both team teams responded at the scene, Dr. Allen Sills, the NFL’s chief medical officer, said.

“It’s certainly not an exaggeration to say that the skilled and immediate response by all of these talented caregivers prevented a very tragic outcome at that moment,” Sills told reporters during a briefing by the NFL on Wednesday.

There has been some speculation in the medical community that Hamlin suffered from commotio cordis, a rare condition that occurs when the heart’s rhythm is disrupted due to a blow to the chest that lands at a very specific moment in the heartbeat.

Knight, from UC Health, said it’s too early to tell if that were the case, but that the condition is “on the list of considerations” while they work through testing.

Sills also said it “certainly is possible” that Hamlin had the condition, but that “there’s still a lot of investigation that needs to happen.”

Commotio cordis is “almost a diagnosis of exclusion,” meaning that no other cause has been found, Sills said. In some cases of cardiac arrest, the cause may go undiagnosed, Dr. Jim Ellis, the NFL’s director of emergency preparedness, said.

“The difficulty you have in this particular case, obviously a 24-year-old, very healthy, fit male, sometimes you just may not find the cause,” he told reporters during a press call. “There’s not always a pathway. You can’t get an MRI, a CT scan, there’s no blood test in particular that’s going to tell you exactly why they had that, certainly nothing for commotio cordis.”

Sills said the league will examine whether any changes need to be made to the players’ protective equipment, as is customary after someone is evacuated from the field. Shoulder pads typically cover the sternum, which is the “major area of interest for prevention” of commotio cordis, he said.

Both doctors commended the quick response on the field.

“I think the important lesson that we can all take away from this is really, for every sport at every level, for preparation for a sudden cardiac event,” including proper training and having automated external defibrillators available, Sills said.

“That is a very, very key message and something we can all learn from,” he added.

Troy Vincent, the league’s executive vice president of football operations, got emotional talking about Hamlin and called the medical response “outstanding.”

“You gave our brother Damar another day to live, another chance to fight,” Vincent said, his voice shaking.

Bills return to practice

Buffalo Bills players returned to their practice facility on Wednesday.

The New England Patriots, who are still scheduled to face Buffalo in Sunday’s final game of the season, said in a statement both teams had been given an extra day before meeting with the media “due to these unique circumstances.”

McDermott told reporters Thursday that the Bills playing their next scheduled game this weekend is what “Damar would’ve wanted.”

Vincent told reporters Wednesday that he is letting the Bills take the lead on whether to postpone the game.

“It’s really important that we just keep the pulse of the coach and the players, and don’t get in front of that,” he said. “And we will allow [Bills head coach] Sean [McDermott] and his team and his staff and the players, which are the most important thing here, to guide us if we have to make that decision collectively with the club.”

The Pro Football Hall of Fame also announced Tuesday night it would be delaying its announcement of the 15 finalists for this year’s class out of respect to Hamlin.

ABC News’ Mark Osborne, Will McDuffie, Matt Foster and Alexandra Faul contributed to this report.

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