Philadelphia, PA (Sports Network) - The Boston Celtics were dealt a horrible blow on what turned out to be an emotional day at the TD Bank Garden Sunday.

The worst fears were confirmed when it was announced Rajon Rondo was done for the season with a torn ACL. He was a late scratch from the starting lineup and frankly no one on the C's thought it was anything that serious.

It shaped up as an awesome Sunday before the news.

Ray Allen returned for the first time in five seasons as a visitor. He got a nice ovation after a video presentation, then was appropriately booed out of the building. Sadly for Boston fans, Allen came back as a member of the hated Miami Heat and just having the defending champs in the building was buzz- worthy.

The Celtics dropped the Heat in double overtime and the mood went from great- to-downtrodden quickly.

"I just walked in and told them," said head coach Doc Rivers of the Rondo announcement. "I don't know what else you can do. Guys were celebrating and then it just ..."

The reality facing the Celtics is a scary one. Few teams can recover from the loss of their best player, but if Boston fans want reason for optimism, look 850 miles west.

The Bulls have been downright brilliant without former MVP Derrick Rose. The reason is simple, the defensive system used by the Bulls survived without Rose.

That's one of the reasons the Celtics are in serious trouble and it started long before Rondo went to the emergency room.

Last season, the Celtics finished second in the NBA in opponents' scoring. This season, they are 11th.

Last season, the Celtics were 10th in the NBA in rebounding. This season, they are 29th.

These flaws existed with Rondo on the floor. Granted, the situation could get worse on both fronts without their general. Rondo is still an above-average to great defender and he is fourth on the team in rebounding.

But these problems have driven the Celtics under .500 and down to eighth in the Eastern Conference, not Rondo's injury.

If playoffs are what you're looking for, the Celtics are still 2 1/2 games ahead of Philadelphia for the final playoff spot, but apparently Sixers center Andrew Bynum could be back before the All-Star break. Much like confirming the existence of a Yeti, we should believe Bynum's return when we actually see it happen. But the Sixers could be on the rise.

How will the Celtics replace Rondo? Is it time to blow the whole Celtics core to smithereens?

If a trade is what you're looking for, there's room to wiggle. Paul Pierce is 35 and still averages 18.7 ppg. He is on the books next season for $15,333,334, but it's a player option and partially guaranteed for $4 million.

Is Pierce willing to move? Doubtful, but would the Celtics even open their minds to moving him? That's equally doubtful. Pierce has been the face of the C's in the post Larry Bird era and there's a lot of equity in the bank between the two sides.

Could they move Garnett? That's trickier. He's almost 37 and has two seasons remaining on his contract that pays almost $24.4 million. That second season on the books would be a big hindrance for teams.

Boston could move some other veteran pieces, but it's unlikely the Celtics would get a lot in return for a Jason Terry (two more seasons under contract) or a Jeff Green (who has a preposterous three years and $27.6 million left).

Young guys like Avery Bradley and Jared Sullinger are in rookie deals still, but they've emerged as cornerstone pieces.

Truth be told, Rondo was probably the best trade chip for Danny Ainge, president of basketball operations. He'll be 27 shortly and has two years left and a very reasonable $24.8 million, which is great for a guy who is one of the three best point guards on Earth.

Short of moving Pierce, which I think is still unrealistic, the Celtics will have to survive from within. The problem with that plan is not that there isn't anyone as good as Rondo on the roster. That's obvious, but Boston barely has a backup point guard on the team.

Courtney Lee started in Rondo's absence on Sunday. He's more of a shooting guard, same with Bradley. Terry played point in his youth, but is also now a two guard. Leandro Barbosa is probably best equipped to play the point for the longest and he's been underutilized by Rivers. Barbosa could help and the C's could still make the postseason.

What good is that? The Celtics, even with Rondo, and notwithstanding Sunday's result, could not eliminate the Heat in a playoff series. Their problems are too deep on the defensive side, not to mention that Terry, Lee and Green haven't appeared to fit in very well and we're already at the midpoint.

"Well you can write the obituary. I'm not," Rivers said on Sunday. "In my opinion, we're going nowhere."

The obituary on the season, in terms of being title threats, was written long before Rondo went hobbled. The obituary on the Celtics as formidable playoff contenders past this season is still unwritten.

But the cap is coming off the pen, or, in the parlance of 2013, the fingers are hitting the keyboard.

RANDOM THOUGHTS

- As to who replaces Rondo in the All-Star game, with only three other guards on the roster, my hunch is Brooklyn's Deron Williams gets the call and maybe Kyrie Irving starts.

- Chris Bosh told FOX Sports Florida on Friday that he is absolutely a Hall of Famer. To be specific, he said, "Hell, yeah, of course. I've been a Hall of Famer like four years ago." That second part is silly, but is he a Hall of Famer right now? At first, Bosh doesn't pass the first test, which is saying it aloud and reacting. So, doing research, Bosh has career averages of 19.7 ppg and 9.0 rpg. He posted five 20-plus seasons prior to moving to Miami in the effort of being a good teammate. Bosh has been to eight straight All-Star games, but made only one All-NBA team, a second-team honor in 2006-07. That was the only season he finished in the top 10 of MVP voting. So, to sum up, hell no, he's not a surefire Hall of Famer.

- Royce White was reinstated by the Houston Rockets and reported to the D- League. The Rockets met White on some demands, but didn't cave on all of them. Compromise - it can work.

- Forgive me if I'm not giddy about the Los Angeles Lakers' win Sunday over the Oklahoma City Thunder. It's one game and they aren't getting any more athletic as the season progresses.

- Reports say the Texas Legends of the D-League are making a serious run at Allen Iverson. "The Answer," 37, shouldn't come up to further tarnish his playing legacy, but money is always an issue for Iverson. No doubt, he still thinks he can contribute to an NBA team, but reality says almost exactly the opposite. Veterans are playing more in the D-League to try to get back to the big show, but when guys like Mike James and Delonte West do it, they have nothing to lose. When Iverson does it, it gets remembered and could stain what people think of him as a superstar. If he needs the loot, he shouldn't let pride get in the way.

- Movie moment - It used to be a fun game when I worked in the golf room to discuss what media coverage would be like for fictional events. The game was mostly spawned from "The West Wing," but how do you think the smart phone footage of a bunch of 10-year-olds drinking beer would play at the end of "The Bad News Bears?" "This scene from a Little League championship, the losing Bears seen drinking beer and throwing beer bottles at the winners. Horrifying as the parents look on."

- TV moment - If you were wondering why the Pro Bowl still exists as I was, I went searching for answers. Sunday is a pretty big night for television and the Pro Bowl stills get the ratings. I haven't seen a full quarter of the Pro Bowl in my 36 years on Earth. Proud of it. So, we have the citizens of the United States to blame for the Pro Bowl still being a thing.

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