Damar Hamlin gives 'perspective' on sport's dangers
Players stood stunned with tears in their eyes as medical officials performed CPR on the Hamlin in the middle of the field, an incident that horrified fans and prompted the NFL to postpone the game.
Seven-times Super Bowl winner Tom Brady said on social media that the moment "put into perspective what it means to play this game we love".
For competitors from other disciplines who suffered their own life-threatening injuries, Hamlin was a jarring reminder of how vulnerable athletes can be.
"Prayers that Damar Hamlin can have the same outcome that I was fortunate to have with my incident," retired National Hockey League (NHL) defenceman Chris Pronger wrote on Twitter.
Pronger, who collected two Olympic gold medals for Canada, collapsed and suffered a cardiac arrest when a slap shot hit him in the chest at the 1998 Stanley Cup playoffs. He was able to continue his career, playing for more than a decade after recovering from the incident.
"Our thoughts and prayers go out to Damar, his family, teammates and the greater NFL community during this incredibly scary time," he added.
Others have been less fortunate.
Former Bolton Wanderers midfielder Fabrice Muamba was forced to retire at the age of 24 after collapsing on the pitch in an FA Cup match in 2012 and being technically "dead" for 78 minutes. The match was abandoned.
He was saved in part by the intervention of an off-duty heart specialist in the crowd who used a defibrillator to revive the player's heart, leading to a campaign to have more of the emergency devices made available at sports clubs and public places.
In January last year, he said he was worried by the prospect of Christian Eriksen returning to the Premier League, following the Denmark international's cardiac arrest on the pitch at the European Championship in 2021.
Eriksen collapsed in the 42nd minute of a Euro 2020 match against Finland and was later taken to hospital. He was then fitted with a special heart-starting device known as an Implantable Cardioverter Defibrillator (ICD).
The 30-year-old was forced to terminate his contract with Inter Milan in December 2021 because footballers fitted with an ICD are not permitted to play in Italy's Serie A. He has since played for Brentford and Manchester United.
Almost two hours after he left the field, the Denmark v Finland game resumed, taking place in an understandably subdued atmosphere as Finland won 1-0.
Players and the Danish coach later complained that UEFA had offered them the option of resuming that evening or beginning again the following lunch time.
UEFA defended their decision, saying they acted with the utmost respect and ordered the restart after consultation with the players.
In 2003, midfielder Marc-Vivien Foe collapsed in the 72nd minute of Cameroon's 1-0 victory against Colombia in a Confederations Cup match in Lyon, France and died shortly afterwards.
Medics spent 45 minutes trying to restart Foe's heart before he was pronounced dead. His autopsy found the Olympique Lyonnais player suffered from hypertrophic cardiomyopathy, a hereditary condition which increases the risk of collapse during exercise.
In cycling, Belgian rider Michael Goolaerts died after suffering a cardiac arrest during the Paris-Roubaix cycling classic in 2018.
Canadian-born Italian ice hockey player Darcy Robinson died after suffering a heart attack and passing out during a top-flight match in Italy in 2007.
Australian cricketer Philip Hughes died two days after being struck in the head by a ball while batting in a domestic match in 2014. That game was called off after Hughes collapsed and required emergency treatment.