Tim Duncan retired a few seasons ago, Tony Parker signed with the Charlotte Hornets and Kawhi Leonard has been traded to the Toronto Raptors. Now, the last remaining key player from the Spurs' championship teams may be ready to call it quits. According to a report from ESPN's Adrian Wojnarowski, Manu Ginobili is "seriously considering" retirement. 

Ginobili, who has spent his entire career with the Spurs, is under contract for the upcoming season. And per Wojnarowski, the 41-year-old's been working out at the team's facility in preparation of playing, but still hasn't made up his mind about whether he'll actually do so. Via ESPN:

San Antonio Spurs guard Manu Ginobili, a future Naismith Basketball Hall of Famer, is seriously considering retirement and plans to meet with coach Gregg Popovich in the coming days to discuss his future, league sources told ESPN.

Ginobili, 41, has been working out regularly at the Spurs practice facility and hasn't made a final decision on the coming season, but sources say that he's strongly confronting the possible end to an historic 16-season run with the Spurs that includes four NBA championships.

Ginobili is obviously not the player he once was, but he proved last season that he can still be a helpful asset for the Spurs. In 65 games, he averaged 8.9 points, 2.2 rebounds and 2.5 assists. The question Ginobili will have to answer is whether he wants to do everything that's necessary in order for him to still play at this level -- the workouts, treatment, diet, etc. -- for a team that likely won't be a title contender. And not only that, but he'll be without most of his longtime teammates and friends.