Tim Duncan is "leaning strongly" towards retiring after 19 seasons in the NBA with the San Antonio Spurs.

Duncan has left team officials, close associates and friends with a strong belief he's preparing to make an announcement in the near future on his departure.

Duncan recently elected to exercise the $5.6 million player option on his 2016-17 contract – a payment the Spurs could still make to Duncan regardless of whether he plays or retires.

San Antonio has been aggressively pursuing Pau Gasol.

Duncan, who has long had trouble with his left knee, was slowed during the season with soreness in his right knee.