Ben Simmons and the Philadelphia 76ers remain at an impasse, as the two sides have been since Philadelphia was eliminated in the second round of the playoffs by the Atlanta Hawks in June.

Simmons, who is under contract for four more seasons, would like to be traded. The 76ers would like to trade him, but only for a return they believe is commensurate with how they value the 25-year-old three-time All-Star and two-time All-Defense selection.

So far, a deal hasn't happened. Until it does, both sides will remain locked in a stalemate.

Sources previously told ESPN's Adrian Wojnarowski that Simmons has sought a trade out of Philadelphia and that Simmons' agent, Klutch Sports CEO Rich Paul, and Sixers management met earlier this summer. Now, sources confirmed Simmons has threatened to skip the start of training camp in an effort to put pressure on Philadelphia to make a move.

All of that adds up to Philadelphia -- a city that has grown accustomed to drama surrounding its basketball team -- being home to the league's stickiest situation with less than three weeks until training camp.

How did we get here?

From the moment Simmons passed out of a wide-open dunk to Matisse Thybulle with under four minutes to go in Game 7 of the Eastern Conference semifinals against the Hawks, league insiders have believed his exit from Philadelphia was inevitable.

After staunchly defending Simmons all season, Sixers coach Doc Rivers was asked after that Game 7 loss if Simmons could be a championship-level point guard.

"I don't know the answer to that," Rivers said.

Part of the reason Rivers defended Simmons all season was that it was his latest attempt to use his news conferences to boost the confidence of one of his key players -- something he'd had success doing with players like Rajon Rondo with the Boston Celtics and DeAndre Jordan with the LA Clippers.

Not only was Philadelphia still hoping Simmons would become more willing to shoot, but there also was the fact that Simmons' name had been bandied about in James Harden trade talks at the start of the season.

Ultimately, none of it worked, culminating with Simmons passing up that wide-open dunk.

Shortly after that ugly Game 7 loss, and following a discussion between management and Simmons' representation, both sides agreed to look for a trade as the draft and free agency approached. Over the ensuing weeks, the Sixers had talks with numerous teams, sources said, and several made what they believed were legitimate offers.

It became clear the Sixers' asking price for Simmons was steep; Philly was looking for a premium return whether it was a star player, multiple first-round picks or both.

After the transaction season ended in mid-August, owner Joshua Harris and 76ers management flew to Los Angeles to meet with Simmons and agent Rich Paul. The Sixers intended to tell Simmons they couldn't find a deal for him and hoped to put aside differences and enter the season on the same page, sources said.

Simmons, however, was steadfast, telling Harris he didn't want to play for the team again and that if he wasn't traded by the end of the month he didn't intend to come to training camp, sources said.

The point was made that it wasn't Simmons' responsibility to increase his trade value, and that the Sixers should find the best possible trade and execute it now, rather than wait for a strong start to the season to increase his value.

Why hasn't Simmons been traded yet?

The simple answer? Because Damian Lillard and Bradley Beal aren't available yet.

Philadelphia's president of basketball operations, Daryl Morey, has proven three things over his long, successful run as an executive: He isn't afraid of awkward situations, he isn't going to make a deal for the sake of making one and he is constantly trying to swing trades for stars.

Like several other teams around the league, the 76ers are closely monitoring the Lillard situation in hopes that he asks out of Portland. Earlier this summer, Lillard said he didn't feel like the Blazers had a championship roster and wanted to see improvements. Portland has had a quiet offseason in terms of free-agent additions.

Until there's any movement there -- or another team comes in with a huge offer for Simmons separately -- it seems likely Simmons will remain on Philadelphia's roster for the foreseeable future.

Would Simmons really not report to training camp?

Rich Paul hasn't been afraid to use this sort of tactic to his advantage in the past. Two Klutch Sports clients, Tristan Thompson and JR Smith, had protracted contract negotiations with the Cleveland Cavaliers deep into training camp, only getting them done close to the start of the regular season.

This situation is different. Simmons is under contract for another four seasons, which diminishes his leverage. Holding out is one way he could pressure Philadelphia to make a move -- although it's unlikely Morey would feel the need to rush into making one.

Expect the NBA to step in if Simmons does not report and the 76ers do not penalize him financially with a suspension. The last thing the league can afford is a precedent of players under contract not reporting for training camp.

Have there been recent examples of players under contract not reporting to camp?

The closest is Jimmy Butler in 2018 with the Minnesota Timberwolves. Butler was dissatisfied that his contract was not renegotiated during the offseason and believed not everyone on the roster was aligned to winning. As a result, he implored the organization to trade him.

The Butler situation was different because the Timberwolves gave him permission to miss media day and the early part of training camp while he rehabbed his right knee. When Butler did return to training camp on Oct. 10, he created a storm at his first practice, challenging teammates, coaches and front-office executives.

One of those targets was then-GM Scott Layden: "You f---ing need me, Scott. You can't win without me," Butler reportedly said.

The young Timberwolves team that reached the playoffs the previous year started the season 3-7. After four straight losses, Butler was traded on Nov. 12 to the 76ers, where he helped Simmons and Embiid reach the second round of the playoffs before losing to the eventual champion Toronto Raptors.

Another example is when the Rockets' James Harden asked for a trade last offseason and missed the first week of training camp as a result of failing to meet the NBA's COVID-19 protocols.

Harden eventually practiced on Dec. 14 but was ruled unavailable for the Rockets' season opener after being spotted at an indoor party without a mask, a violation of the league's health and safety protocols that cost him $50,000. Houston started the season 3-6 before Harden was traded to Brooklyn in mid-January.

A Simmons no-show at training camp would be considered more of an inconvenience and less of a disruption.

Unlike Minnesota and Houston, where Butler and Harden were both their teams' top players, that is not the case in Philadelphia. The 76ers have an MVP candidate in Joel Embiid and a strong nucleus led by Tobias Harris, Seth Curry, Thybulle and Tyrese Maxey.

With or without Simmons, Philadelphia is still a playoff team, although likely not one of the favorites to come out of the Eastern Conference.

What are the financial implications if Simmons holds out?

Under Article VI, Section 1 (player conduct) of the collective bargaining agreement, a player who fails to render services would be suspended and could be fined up to 1/145th of the player's base compensation for each day he does not show up.

This means Simmons could forfeit $227,613 for every practice and game that he misses. It should be noted that Simmons would need to be suspended before the 76ers can levy the per-day penalty.

Taking the suspension approach is the point of no return for the 76ers, who would lose a ton of leverage in their search for a trade.

If the 76ers elect not to enforce the "failure to render services" language in the CBA, they could still fine him $2,500 for the first missed practice, $5,000 for the second missed practice, $7,500 for the third missed practice and a reasonable fine under the circumstances for a fourth (or additional) missed practice.

However, Simmons' situation is unique because of the pay structure in his contract.

When Simmons signed his five-year $177.2 million rookie max extension in 2019, he elected to be paid 25% of his salary for every season on July 1, 25% on Oct. 1 and the remaining 50% in 12 installments starting on Nov. 15.

The unknown is if the 76ers would withhold $8,250,984 on Oct. 1 if he doesn't show up for training camp.

What is Simmons' relationship with Embiid now?

From the moment Simmons and Embiid began playing together in 2017, there have been questions about their on-court fit despite the two of them consistently posting positive net ratings when sharing the court.

Philadelphia's repeated stumbles in the playoffs haven't eased those concerns. And after Embiid spoke to the media following the 76ers' Game 7 loss to the Hawks, the idea of breaking up the stars burst open.

"I'll be honest. I thought the turning point was when we, I don't know how to say it, is when we had an open shot and we made one free throw," Embiid said, not naming Simmons but specifically calling out his passed-up layup opportunity as the reason for Philadelphia's loss.

However, Embiid took to Twitter last week in response to a story about the status of their relationship, saying he had no issues with Simmons.

"Stop using my name to push people's agendas," Embiid tweeted. "I love and hate drama. I love playing with Ben. Stats don't lie. He's an amazing player and we all didn't get the job done. It's on me personally. I hope everyone is back cuz we know we're good enough to win."

ESPN's Ramona Shelburne and Brian Windhorst contributed to this story.