By Matthew Geagan, CBS Boston

BOSTON (CBS) — The Celtics have had bad losses this season. A lot of them. Some would say too many to choose from.

READ MORE: Tom Brady Is Not A Fan Of NFL's Uniform Number Rule Change

There was a 30-point defeat to the Knicks at TD Garden. There was an embarrassing and disheartening loss to the Wizards. There have been blown leads aplenty and quite a few mental collapses throughout Boston’s 26 losses this season.

But we finally have our winner for biggest loser. That would be Tuesday night’s beatdown by the Philadelphia 76ers at TD Garden, a night when the Celtics couldn’t compete with one of the best teams in the East, and really, didn’t want to compete with one of the best teams in the East.

The final score shows just a 10-point loss, but it was much worse and much more painful than that. The game was actually somewhat close midway through the second quarter, until Philly stopped lettings its little brother stay within striking distance and turned on the jets. After that, it was no contest.

The Celtics may have had a chance to keep it close, and possibly respectably, had they not turned the ball over 20 times. The majority of those were unforced errors, making matters much worse. And when Philadelphia upped its own defensive intensity, the Celtics just slumped their collective shoulders and let the loss happen.

Joel Embiid did whatever he wanted, which is nothing new because he is doing whatever he wants to most opponents this season. Robert Williams was served a dose of reality against the MVP favorite, fouling out after just 14 minutes. With Tristan Thompson still out, that left Luke Kornet and Tacko Fall to deal with Embiid, who finished with 35 points on the night. It worked out as well as you can imagine.

READ MORE: Cape Cod Baseball League Approves 40-Game Schedule For 2021 Season

Embiid usually gets his no matter what the other team throws at him. But the Celtics did nothing to stop anyone else on the 76ers, leading to a pretty balanced evening for Embiid’s supporting cast. Ben Simmons really didn’t have to do much, scoring 12 points, because everyone else was hitting their open looks. Boston must have forgotten that Danny Green has made a career out of hitting threes, since the Philly guard canned five of his six attempts from downtown and finished with 17 points.

If Boston’s defensive effort was bad, the offensive effort was worse. Jayson Tatum looked like he wanted no part of Boston’s biggest game of the season, sleepwalking though his 35 minutes. He went 0-for-4 in the first quarter and had just five points at halftime, somehow finishing with a game-high 20. Most of that can be chalked up to a good player scoring points on a bad team.

The Celtics once again relied solely on the three-point shot, with nearly half of their attempts coming from beyond the arc. Boston hit just 14 of its 34 threes, showing zero desire to fight for anything inside.

Philadelphia’s lead ballooned to 21 points, and when the game was over, it was clear that the Celtics are nowhere near the upper tier of the Eastern Conference. They aren’t even in the second tier right now, which is basically just bad teams that aren’t as bad as the really bad teams. At the moment, Boston is a really bad team.

A really bad team that suffered a really bad — and demoralizing — loss on Tuesday night. It was the Celtics’ biggest game of the season, a chance to show that they could maybe still run with a team they’ve sent home from the postseason two of the last three years. Instead, the Celtics went out and stunk it up again, showing no care and little effort as they fell back under .500 for the season.

MORE NEWS: Zurich Classic Preview: Can Jon Rahm And Ryan Palmer Defend Title At TPC Louisiana?

The only thing the Celtics proved is that they’re now miles away from where they should be. If the season wasn’t already lost heading into Tuesday night, it certainly is now.