Rachel Nichols explains that Joel Embiid is talented, but if he continues to struggle with injuries, the 76ers will be in trouble. (2:18)

Philadelphia 76ers center Joel Embiid's five-year, $146.5 million maximum extension is essentially guaranteed but protects the franchise financially should Embiid suffer a contractually specific catastrophic injury, league sources told ESPN.

Embiid, 23, signed the rookie-scale max extension Tuesday, with the $146.5 million total for the deal based on the NBA's new salary-cap projections for the 2018-19 season.

For the Sixers to curb the ultimate value of the extension, it would take the triggering of several severe circumstances detailed in a 35-page-plus contract. Embiid's unique career trajectory -- missing his first two NBA seasons with successive foot surgeries and playing only 31 games in the 2016-17 season -- created a pathway for Philadelphia general manager Bryan Colangelo; Embiid's agents at CAA Sports; and the National Basketball Players Association to work together on creating a complicated and creative contractual agreement. The dramatic impact of Embiid's brief but dominant debut season left him as the only rookie since Wilt Chamberlain to average at least 28.7 points per 36 minutes played.

Here's how a perfect storm of calamity would have to unfold for Embiid to earn any less than the full $146.5 million: Across each of the final four seasons of the extension, ending with the 2022-23 season, the 76ers could waive Embiid for a financial benefit if he's lost because of a contractually agreed-upon injury that causes him to miss 25 or more regular-season games and if he plays fewer than 1,650 minutes, league sources said.

Specific injuries are laid out in the contract and include only past problem areas with Embiid's feet and back, sources said. Embiid has to miss 25 or more regular-season games because of injuries to those areas, and play fewer than 1,650 minutes, for Philadelphia to have the option of releasing him for cost savings.

Joel Embiid missed all of his first two seasons with injuries and was limited to 31 games last season, when he averaged 20.8 points, 7.8 rebounds and 2.5 blocks per game. AP Photo/Aaron Gash, File

For example, if Embiid hypothetically suffered a serious knee or wrist injury -- something outside the contractual language surrounding the feet and back -- the 76ers would have no avenue to waive Embiid to reclaim any portion of his salary. And given Embiid's rare talent, there's a belief that he'd have to suffer a career-ending injury to inspire the 76ers to release him.

If Embiid met that narrow criteria and the Sixers decided to waive him after the 2018-19 season, he would receive $84.2 million of his full contract; after the 2019-20 season, $98.2 million; after the 2020-21 season, $113.3 million; and after the 2021-22 season, $129.4 million.

What's more, if Embiid played a minimum of 1,650 regular-season minutes in three consecutive years during the extension, or three out of four including the 2017-18 season, those benchmarks would eliminate the possibility of a reduction in the contract, league sources said.

The first full season of Embiid's contract extension starts with the 2018-19 season and pays him $25.3 million, a salary that escalates a standard 8 percent per year until the 2022-23 season.

For Embiid to reach the threshold of the super maximum contract criteria -- which would pay him 30 percent of the salary cap and ultimately as much as $176 million -- Embiid must earn first-team All-NBA honors or be voted the NBA's Most Valuable Player in the 2017-18 season.

Despite missing his entire first two seasons with injuries and undergoing season-ending surgery that limited him to 31 games in 2016-17, Embiid showed the promise of being a transformational talent. He averaged 20.8 points, 7.8 rebounds and 2.5 blocks per game last season.

Embiid, the No. 3 overall pick in the 2014 NBA draft, had successive surgeries on his right foot that sidelined him in the 2014-15 and 2015-16 seasons. Surgery to repair a torn meniscus in his left knee ended his 2016-17 season in March. Embiid has yet to make his debut this preseason but recently returned to full-contact participation in practices.

Embiid is expected to be ready to play for the Sixers on opening night on Oct. 18 against Washington but could initially face minute restrictions as part of the rehab process on his knee.

Embiid is the centerpiece of a Sixers revival that will include the debuts this season of the NBA's two previous first overall picks, Markelle Fultz and Ben Simmons. The Sixers signed two veteran free agents this summer, guard JJ Redick and forward Amir Johnson.