Illinois hoops star Kofi Cockburn was TRYING to celebrate after hitting a crucial shot Wednesday — but accidentally clocked the ref in the face instead with a BRUTAL elbow.

In fact, the ref immediately dropped to his knees — and was HOSPITALIZED for further treatment.

Cockburn — 7’0″, 290 lbs — had just hit a put-back floater (and got the foul) in the 2nd half against Michigan … and tried to celebrate with a big Tiger Woods-styled fist pump.

But, ref Lewis Garrison accidentally got in the way … and took a BIG elbow right to the face.

Garrison dropped to his knees and had to be helped off the floor … and after trainers checked him out at the stadium, he reportedly went to a local hospital for further evaluation.

Thankfully, doesn’t seem Garrison’s injuries are too serious … it’s reported the trip to the emergency room was for precautionary reasons — but still, scary stuff!!

As for the game, Cockburn ended up leading Illinois to a huge 71-62 win over the Wolverines — a massive upset.