The Philadelphia 76ers fell into an insurmountable 3-0 hole after losing Game 3 to the Boston Celtics on Friday. The Sixers' season is basically over at this point.

Playing without All-Star guard Ben Simmons, the Sixers have had to rely on All-Star center Joel Embiid to carry the load. Clearly, the Sixers are missing the Aussie's playmaking and elite perimeter defense against Boston's elite wings in Jayson Tatum and Jaylen Brown.

Still, we'll never really know if Simmons' presence would have made a difference. Perhaps the Sixers may put up a bit of a fight than they've shown in this series so far? Or maybe the Celtics would still roll past them just the same?

Nonetheless, this has been the theme of disappointing Philadelphia's 2019-20 campaign. The team has underachieved the entire season and it's likely to be punctuated next week when the Celtics finally put them out of their misery.

The Sixers enter the off-season with tons of questions and are in need of a whole lot of soul searching. Here are five things the Philadelphia 76ers need to sort out this upcoming summer.

Do they still build around Ben Simmons and Joel Embiid?

Ben Simmons or Joel Embiid? Many believe the Philadelphia 76ers should split up their two franchise stars and build a more fitting roster around one of them.

Simmons and Embiid are undoubtedly among the most promising stars in the NBA. However, so far, the two haven't shown that they can mesh well together on the floor. There have been rumors about possible trade scenarios involving both Simmons and Embiid, assuming the Sixers explore the seismic move of dealing one of them.

However, considering the two aren't even in their primes yet, you have to think moving on from one of them may be a bit premature. Likewise, whatever they can get from any deal involving the two will likely take them a step back. It certainly won't elevate them over teams such as the Boston Celtics, Toronto Raptors, and Milwaukee Bucks.

Philadelphia should exercise a ton of caution if they go this route.

Finding a new coach

Brett Brown will likely become the first casualty when Philadelphia gets bounced from the playoffs within the next couple of days. It was certainly a shock for some to see Brown remain as head coach following their second round exit against the Toronto Raptors, although it came via one of the luckiest and iconic game-winners in NBA history.

Nonetheless, for a team aspiring to compete for an NBA championship, last year's early elimination was a disappointment. This season, The Process didn't progress at all. Philadelphia was very disappointing in the regular season. Now, another horrendous 48 minutes separate them from leaving the NBA's premises in Orlando and calling it a season.

In three seasons, Brown still hasn't figured out how to make Embiid and Simmons work well together. He should have at least found a way to make the two franchise stars mesh well together.

The first order of business for the Sixers this off-season is to find the right coach that can make Embiid and Simmons co-exist on the court.

Elton Brand needs to be held accountable, too

As much as the headlines call for Brett Brown's head, GM Elton Brand needs to pay for his sins as well. Remember, Brown didn't build this current iteration of the Sixers. Brand did. Brown can only do so much with this ill-fitted roster.

Brand was handed the keys to a very promising roster with two bright stars in Simmons and Embiid. With the way Philly is looking like right now, it's safe to say this isn't “The Process” that Sam Hinkie envisioned.

Sure, there's justification in doing the Jimmy Butler and Tobias Harris deals Brand did last year. But that obviously backfired after Butler walked away in free agency. Likewise, Butler's departure forced Brand's hand to give a fringe All-Star like Harris his desired max deal — a contract that should only be reserved for franchise superstars. This obviously hasn't panned out so well for them.

To make matters worse, Brand also signed 34-year old big man Al Horford to a four-year $107-million deal, to pair him alongside Joel Embiid. This, however, has done nothing but further complicate the already problematic spacing in Philadelphia's offense.

Also, another move that's often overlooked in Brand's tenure so far is how easily he gave up on No. 1 overall pick Markelle Fultz, who is finally finding his stride with the Orlando Magic. The Magic basically gave up pennies (Jonathon Simmons and a couple of picks) for the 22-year old.

Brand's decision to “speed up” The Process has regressed the franchise. Escaping from this mess they're currently in will be a tall order this off-season.

$287-million problems

The Sixers are stuck with a $287-million problem.

In addition to Horford's hefty deal, Philadelphia also inked Tobias Harris to a five-year, $180-million max contract. Philadelphia is paying $287 million to players who are averaging a combined 19.7 points through three games against the Celtics. That is absolutely inexcusable.

Harris' shooting has abandoned him in this series. He is shooting just 33.7 percent from the field and has yet to connect on any of his 10 three-point attempts so far. This is certainly not the type of production you'd want from a player making $36 million annually.

Horford, meanwhile, has scored just 16 points through three games. The former Boston Celtics center has been a bad fit in Philadelphia. Among Philadelphia's top priorities this off-season should be to move Horford.

Even though he's lost a bit of a step, Horford can still be an effective player in the right situation. However, he's just been so horrible in his first season in Philly that his value has taken a massive hit. They will likely need to dump the veteran alongside a future or young asset to get rid of his horrible contract.

Finding a trade partner for the remainder of the aging big man's deal should be harder said than done.

How to build the right roster around the franchise stars

It's clear at this point that the Sixers made horrible mistakes in their roster construction, especially last summer. Thus, it seems like Philadelphia is back to square one.

As mentioned, trading Horford might just be the first player transaction the Sixers do this coming off-season — that is if they can find a taker for his bad contract. Tobias Harris is ideally a good piece next to Joel Embiid and Ben Simmons as a big forward who can stretch the floor and also create shots. And even though the Sixers are going to overpay him over the course of four more seasons at most, he should still be a key piece for them moving forward.

It goes without saying that the Sixers need to surround this team with as much shooting as possible. The front office will need to be super creative in salvaging this horribly constructed roster as we speak.