Buffalo Bills player Damar Hamlin has made his first public appearance since going into cardiac arrest after making a tackle against the Cincinnati Bengals three weeks ago.

Hamlin waved to fans from a stadium suite on Sunday as the two teams met again for an AFC divisional play-off game, which the Bengals won 27-10.

The crowd at Orchard Park stadium erupted when an image of the recovering Hamlin filled the massive screens at the end zones near the end of the game's first half.

Fans turned toward the glass-enclosed suite and cheered.

Hamlin, wearing a hooded jacket, stood in front of the windows and raised his arms as if saluting the crowd and encouraging it to get on its feet.

He ended by forming a heart sign with his hands, his signature gesture.

Earlier on Sunday, the Bills posted a video to both Instagram and Twitter showing Hamlin arriving at the team's locker room and the message "Welcome home, Damar".

The video showed Hamlin arriving in a golf cart about an hour before kick-off, wearing sunglasses and a face covering, with the hood of his jacket pulled up.

He was accompanied by his seven-year-old brother, Damir, and mother, Nina.

He was not seen on the field before the game got underway in snowy conditions.

The Bills made no announcement about his whereabouts to fans in attendance, but word of his attendance had clearly spread by the time he appeared.

Hamlin, 24, had not been seen in public since the Bills and Bengals last met on January 2 in a game that came to an abrupt halt and was eventually cancelled after Hamlin's collapse on the field in the first quarter.

Bills coach Sean McDermott said Hamlin began making regular visits to the team's facility soon after his release from the hospital in what he described as "dipping his toe back in here and getting on the road to just getting back to himself".

His presence was enough to uplift his teammates, who after Hamlin's collapse surrounded him as medical teams used CPR and an automatic external defibrillator (AED) to restart his heart.