The Boston Celtics made a big mistake in Game 4 of their playoff series with the Philadelphia 76ers, and James Harden made sure to emphasize that after the Sixers' crucial win on Sunday.

Harden drained the game-winner for the Sixers in overtime after Joel Embiid found him alone on the right corner with just 20 seconds left on the clock. The star guard shouldn't have been left without anyone guarding him, but Jaylen brown opted to help in the double-team on Embiid that paved the way for Harden's clutch shot.

The Sixers playmaker shared that he's used to draining those corner triples, so it was an easy shot for him with all the space and time he had. He also credited Embiid for dishing an MVP-caliber pass.

“It was supposed to be a dribble and off with for me but Jaylen Brown denied me. So, I just gave Joel space. Jaylen Brown helped and Joel made a hell of a pass, an MVP pass. I shoot that shot every day,” Harden explained.

It was definitely a massive brain-fart for Jaylen Brown. After all, why would he leave someone who has scored 39 points and made five of his eight 3-point attempts at that point unguarded? He was basically asking James Harden to shoot it, to which the Sixers star gladly obliged.

RECOMMENDED (Article Continues Below)

Not to mention that Harden was the one who sent the game to overtime after he drained the clutch floater with 16 seconds left in the fourth. Harden was on fire, but the Celtics really didn't bother guarding him in crunch time.

In the end, the Celtics can blame no one but themselves for their epic collapse.