Buffalo Bills defensive back Damar Hamlin remains in a Cincinnati hospital in critical condition after collapsing on the field during a National Football League game Monday night after suffering a suspected cardiac arrest from a strike to the chest, ESPN reports.

Hamlin collapsed backward seconds after standing up after he tackled an opponent in a game against the Bengals.  He laid on the field for 16 minutes as medical personnel used CPR and applied supplemental oxygen, with the league reporting they were able to restore Hamlin’s heartbeat while still on the field.  Although doctors treating Hamlin have not released a statement about what happened, other physicians have noted what happened to Hamlin is consistent with a condition called “commotio cordis,” where the heart stops beating normally after a collision or hit at a specific point in the pumping cycle.

In the hours after Hamlin’s collapse, NFL fans and players voiced their support for the player and his teammates, traumatized by the event that strickened their colleague.  Most teams canceled their media availabilities Tuesday in respect for the league; Pittsburgh’s head coach, Mike Tomlin, spoke to the media, noting that he’s known Hamlin since the player was a young 12-year-old football fan and voicing the team’s and the league’s support.

Hamlin’s charity, the Chasing M Foundation, a GoFundMe drive to provide toys for children in Hamlin’s hometown of McKees Rocks, Pennsylvania had $2,500 in it before the incident.  As of 8:30 p.m. ET, the page had more than $5.4 million in pledges from nearly 187,000 donations.  Among the new donations:  Tampa Bay quarterback Tom Brady and professional wrestler Chris Jerricho each gave $10,000.

The NFL hasn’t rescheduled game, announcing that it will not be played this week.  Both the Bills and the Cincinnati Bengals are in the heat of playoff races, with the outcome of the matchup influencing playoff pairings in two weeks.