The surgery "could sideline him for three months," according to ESPN's Adrian Wojnarowski.
Millsap is in his first year with the Nuggets after signing a two-year, $60 million deal in the offseason that includes a club option in 2019. While he earned an All-Star appearance in each of the last four seasons with the Atlanta Hawks, he was off to a bit of a quiet start this year with averages of 15.3 points and 6.2 rebounds per game.
These marks would be the lowest since 2012-13 with the Utah Jazz. His 29.7 minutes per game is also his lowest since 2009-10.
Bleacher Report's Adam Fromal discussed the Nuggets' ability to move on without him:
Kenneth Faried and Mason Plumlee project to get more minutes in the frontcourt alongside Nikola Jokic. After a 10-7 start, the team is on its way toward its first playoff appearance in five seasons.