Milwaukee Bucks news: Unfortunately for the Philadelphia 76ers, the James Harden trade saga has spilled over to the regular season. The Sixers were unable to resolve the matter during the summer, and it has now reared its ugly head at the first possible opportunity.

With Philly opting to have the former NBA MVP sit out Thursday’s season-opener against the Bucks, the NBA has decided to launch a formal probe on this controversial development.

According to reports, Harden rejoined his team for practice on Wednesday — two days prior to their matchup against the Bucks in Milwaukee. Apparently, Harden had his bags packed with the intention of joining the team for their two-game road trip to open the season.

The Sixers, however, reportedly rejected Harden’s plan to suit up for Thursday in Milwaukee and on Saturday against the Toronto Raptors. Apparently, the team wants the 10-time All-Star to remain in Philadelphia to work on his conditioning. This is after Harden skipped pretty much the entire preseason.

The Sixers’ first home game of the season is on Sunday against the Portland Trail Blazers, and it remains to be seen if Harden will be available for that one.

It is now being reported that the league has decided to launch a formal investigation into Harden’s absence from Thursday’s game against the Bucks:

“We are looking into the facts around James Harden’s availability tonight to determine whether an approved reason exists for his lack of participation,” league spokesman Michael Bass told Adrian Wojnarowski of ESPN.

The Sixers are officially calling Harden’s absence as a “personal matter,” which obviously, hasn’t sat too well with the league and their new policy aimed at increasing star players’ availability throughout the season.