Embiid scored a career-best 59 points, with a joint career-high seven blocks, along with 11 rebounds and eight assists.
The Cameroonian scored 26 of Philadelphia's 27 final quarter points and more than half their total score, a feat not achieved in the NBA since Damian Lillard in 2019.
"I've seen a guy score a lot of points," Rivers told reporters. "I haven't seen guys score a lot of points, rebound, and then the blocked shots. That was impressive.
"He was just getting everything. I've never seen a more dominating performance when you combine defense and offense."
Embiid's teammates were left in awe too, with Matisse Thybulle labelling his stat line as "pretty ridiculous".
"It’s absurd. Actually, my friends were texting me after the game and they were like 'It's like a 2K stat line' and it's not one of those things you see in a real basketball game," Thybulle said.
"It's like when you pick one player on 2K and just do everything with him. It's pretty ridiculous if I'm being honest. It's amazing."
Despite his monstrous performance, Embiid played down the significance of his individual display.
"This is not about me. We did it as a team," the 28-year-old center said. "Obviously, the coaches put me in those positions, and obviously, my teammates fed me the ball. I thought we had great spacing around everything we were doing.
"Like I said, all the credit goes to my teammates just being in the right spots and trusting me and giving me the ball."
Embiid shot 19-of-28 from the field including making a three-pointer, which reinforced to him that it was going to be his game.
"When I finally made a three [I knew it was going to be a big game] because I’ve been shooting the ball so bad this year from three," he said.
"It was early in the game. I saw how they were guarding me. Just like last night, I'll take that every night. If they’re not gonna double team as much, I hope every team does it so I'll take it, but from the beginning... Obviously, in the fourth quarter with the game being so close, I just wanted to do whatever it took."