Brooklyn Nets All-Star guard Ben Simmons and his former team, the Philadelphia 76ers, reached a settlement agreement on the grievance Simmons filed to recoup a portion of the nearly $20 million withheld from him as a result of his failure to play games in the 2021-2022 season, sources told ESPN on Monday.

Both sides agreed to confidentiality on the exact financial settlement reached, sources said.

Simmons and the National Basketball Players Association filed the grievance in April after the discussions between Simmons' representatives at Klutch Sports and the 76ers didn't result in a settlement, sources said. The sides entered into an arbitration process but reached a settlement agreement prior to a judgment.

Philadelphia had repeatedly insisted that Simmons was in breach of his contract under the collective bargaining agreement between the NBA and NBPA and had the right to recoup the money advanced to him before the season. After Simmons made a trade request, the 76ers maintained Simmons breached his player contract upon failing to show up for the start of training camp and refusing to play during the preseason and regular season.

Simmons arrived in Philadelphia near the end of preseason but cited his mental health as the reason his participation in team activities was so limited. The 76ers and Simmons disagreed over the degrees of access that the team and its doctors were allotted to Simmons to diagnose and affirm his mental health, sources said.

Simmons received his full salary for his time spent with the Brooklyn Nets after a Feb. 10 trade, although he never played a game for Brooklyn. Simmons had surgery to repair a disc injury in April and is expected to be ready for the start of training camp in late September.

Simmons and his agent, Rich Paul of Klutch Sports, requested a trade in a postseason meeting after the three-time All-Star guard had a falling-out with the team upon a poor performance in an Eastern Conference finals loss to Atlanta.

Simmons, the No. 1 pick in the 2016 NBA draft, has been one of the league's top defenders and signed a five-year, $170 million maximum contract in 2019.

Beginning with Simmons' first paycheck on Nov. 15, Philadelphia began to take back the per-game salary of $360,000 for each game Simmons missed in the season. Because Simmons received a $16.5 million advance of his $33 million salary in the offseason, there wasn't enough money in each paycheck to cover the per-game deductions.

The back injury first affected Simmons during the spring of the pandemic-interrupted 2020 season. He also reported discomfort in his back upon reporting to Sixers training camp in October. The injury was assessed and treated by Philadelphia's team doctors, and he was cleared to resume basketball activities shortly thereafter.

That period was the only time Philadelphia did not find Simmons in breach of his contract last season, sources said.

Bobby Marks and Ramona Shelburne contributed to this report.