After Manu Ginobili announced he would return to the NBA, and then later clarified on social media that his 15th season would be with the San Antonio Spurs, that left All-Star and two-time MVP big man Tim Duncan’s status as the only glaring question mark in San Antonio’s offseason reshuffle.

Head coach Gregg Popovich’s squad is coming of a franchise record 67-win season, one that unceremoniously ended in a second-round playoff loss to the Oklahoma City Thunder in six games, but plans to somehow build off or maintain last season’s success are sort of in limbo until Duncan decides whether or not to return for a 20th season or retire.

According to the San Antonio News-Express, Spurs officials are eagerly anticipating the five-time champion's choice and its very possible the team even waives the 40-year-old so he can collect all of his salary for next season. The move would also help the Spurs clear out some salary-cap space.

The report indicates that, should Duncan opt for retirement, San Antonio wants to make sure he takes home all of his scheduled $6.4 million in earnings for the 2016-17 season. On Monday, Adrian Wojnarowski of The Vertical reported that Duncan is "leaning strongly towards retirement."

After coming to terms on a two-year, $30 million agreement with veteran power forward Pau Gasol, who will earn $14.6 million next season, the Spurs presently have a $92.2 million payroll and more than $8 million in luxury tax space, according to Spotrac. Those figures do technically include the 38-year-old Ginobili’s $4.4 million cap hold, but he could ask for a raise.

Judging by Duncan’s history, specifically how amenable he’s been to rework his contracts or even take less money to afford the Spurs more cap flexibility to chase down free agents like LaMarcus Aldridge, retirement for the sake of the team cannot be ruled out. The News-Express points out Duncan’s projected salary for next season will count against the cap, but retirement means the Spurs could also breakup the payments overtime to create space this season and beyond.

From a strictly basketball perspective, Duncan is coming off his poorest statistical season. He put up a career-low 8.6 points on 48.8 percent shooting and pulled down 7.3 boards over 25.2 minutes per contest.

However, the 6-foot-11 Duncan was effective on the other end of the floor with a 96 defensive rating, which equals his career average. Duncan’s 3.6 defensive win share last season, though, clearly indicates he’s no longer one of the better defenders in the league anymore.

Still, it’s quite difficult for Duncan, any of his Spurs teammates, the organization, or any of the team’s supporters to envision AT&T Center without him. The decision is reportedly weighing heavily on Duncan, and for good reason.

Even though he’s lost a step, with Aldridge, Kawhi Leonard, and Tony Parker still the beating heart of the squad, San Antonio is part of a handful of teams capable of winning the championship next season. Duncan clearly knows this and the fact that he could miss out on another title is likely the biggest sticking point to his decision.