Tim Duncan exercises option, still mulling future

The San Antonio Spurs have been notified that Tim Duncan has decided to opt into his $5.6 million contract for 2016-17, but that he's still undecided about whether to return for a 20th NBA season, according to a source close to the situation.

Duncan, 40, saw a drop-off in productivity last season, averaging a career-low 8.6 points and 7.3 rebounds in 61 regular-season games and then putting up 5.9 points and 4.8 rebounds over 10 playoff games.