PHILADELPHIA — Joel Embiid is no Joe Namath. Or Mark Messier, for that matter.

After guaranteeing his 76ers would rally to win their first-round series against the Knicks following a Game 2 collapse, Embiid had to watch his vow backfire.

And his season is over, thanks to a 118-115 Game 6 loss at Wells Fargo Center.

“It sucks to lose,” Embiid said. “The goal is to win a championship. Anytime that don’t happen, that’s all I care about. I don’t care if I got to the second round; that does not mean anything to me. We just didn’t accomplish what we wanted to. And the thing is: We believe in ourselves so much that we believed that we actually could’ve won it. But everything didn’t go the way we wanted it to.

“A lot of different circumstances. … Got to be better as basketball players. I’ve got to be better, starting with myself. The whole series I could’ve played better. Maybe if I was better, we would’ve won it, so that’s on me. That’s why we lost. So just got to find a way to get better as a basketball player, as a person, as a leader and come back and hope that everything else aligns.”

The 76ers missed the Eastern Conference final for the 23rd straight year.

But after reaching the second round in five of the last six, they fired Doc Rivers and hired Nick Nurse to get them over the hump. Instead, they lost in the first round.

That was despite Tyrese Maxey earning NBA Most Improved Player honors last week and Embiid coming back from knee surgery with a strong series.

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Embiid had 39 points and 13 rebounds despite clearly not being at his best.

“Man, never give up. Gotta gotta keep your goal,” Embiid said. “Yeah, can’t feel sorry for myself. As long as I can play and jump even a little bit and I can be on the floor, I feel like my presence is enough even if I can’t jump and I can’t move the way I want to, or if my body’s not responding the way it should be. But I just love to play.

“I felt like coming back this year, man, I could’ve taken more time to heal and get back to myself. But the fact [Maxey] is on the team and I’ve known him a long time, I just felt like I didn’t want to give that up. I wanted to get that opportunity to be on this stage and be part of it. And I didn’t want to let him down and the whole team too.”

Embiid also gave props to the 76ers fans for their support in their season finale after criticizing them in Game 4.

“Fans were amazing tonight. Obviously that jumped on us. They got on a run. But it’s a game of runs,” Embiid said. “We made our run and the fans did respond.”