On Wednesday, Adrian Wojnarowski of ESPN reported Ginobili is "seriously considering" ending his basketball career, but he hasn't made a final decision.
The 41-year-old Argentina native was drafted by the Spurs in the second round of the 1999 draft and proceeded to spend his entire career with the organization.
In May, Ginobili said he wasn't prepared to make an immediate decision about his future after San Antonio was eliminated from the playoffs by the Golden State Warriors, but noted retiring was an option.
"I've been contemplating retirement forever," he told reporters. "Nothing changed. I'll let a month or two months go by, and then I'll see how I feel. I'm not the type of guy that makes decisions on the fly, or when you're upset or hurt or whatever. I usually let it sink in and see how it feels."
He's the last player still on the Spurs' roster from its vaunted Big Three. Power forward Tim Duncan retired after the 2015-16 season, while point guard Tony Parker left the franchise in July to sign with the Charlotte Hornets as a free agent.
Ginobili, who has one year left on his contract should he decide to return, averaged 8.9 points, 2.5 assists and 2.2 rebounds across 65 appearances off the bench last season.
His playing time would likely be limited next season, however, because of a San Antonio backcourt that also features DeMar DeRozan, Dejounte Murray, Patty Mills, Marco Belinelli and Lonnie Walker IV.
If Ginobili walks away, he'll do so with a resume that features four NBA championships, two All-Star Game selections and a Sixth Man of the Year Award.
He also starred for the Argentine national team en route to a gold medal at the 2004 Summer Olympics.