This injury could have earth-shattering residual effects across the NFL.

Chiefs All-Pro tight end Travis Kelce went down with what coach Andy Reid is calling a hyperextended knee, and his status for Thursday’s season opener against the Lions is uncertain while he undergoes further testing.

At least one former NFL doctor, David J. Chao, is fearful of another significant injury to a superstar.

“Worst case: 3 letters starting with “A,” he tweeted, explaining that this knee hyperextension could actually show itself to be the dreaded torn ACL that will ruin many fantasy football teams and potentially crater the Chiefs’ Super Bowl aspirations.

Chao was the former head team physician for the San Diego Chargers from 1997-2013.

The 33-year-old Kelce is an eight-time Pro Bowl selection and two-time Super Bowl champion.

He has seven consecutive 1,000-yard seasons and is quarterback Patrick Mahomes’ best option in the Chiefs’ passing game.

The defending champs are also missing their star defensive player Chris Jones, due to a contract dispute.

Reid said there has been “no progress” with the Defensive Player of the Year runner-up.

“We’re focused on the guys who are here. If you’re not there, you’re not there,” he said.