Austin Reaves Tells Fan to 'Shut the F*** Up' After Mocking Luka Doncic Injury

3:05 PM PDT -- Bad news, Lakers fans ... Luka Doncic will miss the remainder of the regular season after suffering a left hamstring injury during Thursday's game.

His status for the playoffs remains uncertain.

His agent, Bill Duffy, said in a statement that Doncic's historic season should still be considered for the league's end-of-the-year honors like MVP ... and they will apply for the "Extraordinary Circumstances Challenge" to the 65-game eligibility rule.

"His record-breaking season deserves to be noted in the history books, despite last night’s unfortunate injury and other extraordinary circumstances," Duffy said.

"We look forward to working with the NBAPA and the league office to ensure a fair outcome in this matter."

Austin Reaves unloaded on a fan during the Lakers vs. Thunder game on Thursday ... telling a guy to "shut the f*** up" after making fun of Luka Doncic's injury.

The heated exchange went down at the Paycom Center in Oklahoma City, when Doncic was laying on the hardwood after suffering a hamstring injury in the third quarter.

As Reaves, LeBron James, and other Lakers gathered around the Slovenian superstar, a man in attendance can be heard on video shouting, "Now you know what it's like to play defense!"

That pissed Reaves all the way off.

"Shut the f*** up," Reaves yelled at the fan. "Shut up. He's f***ing hurting."

The fan actually fired back with a "f*** you," sparking a brief back-and-forth before the Lakers hooper walked over to him.

"That's some bulls***. That' some bulls***. Have some f***ing respect. Have some respect," Reaves said.

Lakers staffers eventually pulled Reaves away, while James stood in front of the fan, shooting him a cold stare before walking off.

Of course, Doncic going down right now is concerning -- the NBA playoffs start on April 18.

Doncic averages 33.5 points and 8.3 assists per game, leading the league in scoring.