Damar Hamlin, who plays safety for the NFL’s Buffalo Bills, received CPR and was carted off the field in an ambulance on Monday night, after collapsing to the ground following a tackle against Cincinnati Bengals receiver Tee Higgins.

The hit came in the first quarter of the game in Cincinnati.

Hamlin reportedly hit Higgins on a play, stood to his feet, then crumpled to the ground.

First-responders rushed on field and administered CPR, before driving the injured safety away in an ambulance.

“Have never seen what’s happening in this Bengals-Bills game,” sports journalist Jemele Hill wrote on Twitter on Monday. “Player has been down for several minutes and is receiving CPR, according to the broadcast. This is truly terrifying. Praying for Damar Hamlin.”

Players on both the Bills and the Bengals could be seen kneeling, crying, standing near Hamlin, and praying as the player received treatment.

Hamlin needed both an automated external defibrillator and CPR on field, and left the field with a pulse but unable to breathe on his own, Fox 19 reports.

The injured player is being taken to the University of Cincinnati for treatment, according to Fox 19.

“The entire City of Cincinnati is sending all of our prayers to Damar Hamlin right now,” Cincinnati mayor Aftab Pureval said on Monday in a statement. “Our hearts are with you, your family and your friends.”

The game between the two teams has been postponed, the Bengals announced on their Twitter page.

“The NFL Players Association and everyone in our community is praying for Damar Hamlin. We have been in touch with Bills and Bengals players, and with the NFL,” the organisation said in a statement,” ESPN reports. “The only thing that matters at this moment is Damar’s health and well being.”

Once he arrived at the hospital, Hamlin reportedly had to be intubated and was listed as in critical condition.

Critics slammed the NFL for the lengthy pause between when Hamlin went down and when the game was ultimately postponed.

“Imagine you’re a football player watching this,” writer Wajahat Ali wrote on Twitter on Monday. “The NFL, as an organization, has refused to call the game an hour after your colleague and brother went down on the floor and had to receive 9 minutes of CPR. This is what they think of you. Just a gladiator. An animal.”

“CALL THE GAME,” in reference to the NFL matchup, quickly became a trending topic on social media following the on-field scare.

Fox Sports anchor Skip Bayless discussed the ramifications of cancelling a game so late in the season.

“This late in the season, a game of this magnitude is crucial to the regular-season outcome ... which suddenly seems so irrelevant,” he wrote on Twitter on Monday.

Soon after the injury, a toy drive that Mr Hamlin organised through his Chasing M’s Foundation was flooded with hundreds of thousands of dollars in donations on GoFundMe, as fans left messages offering messages of support.

As of Monday evening, neither team reportedly planned to hold a formal press conference.

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