According to the Vertical's Shams Charania, Mike Miller and the Denver Nuggets have agreed on a two-year, $5 million deal.
Free agent Mike Miller has agreed to a two-year, $5M-plus deal to return to Denver, league sources tell The Vertical.— Shams Charania (@ShamsCharania) July 19, 2016
Miller played just 373 minutes last year but is widely considered one of the best mentors and locker room leaders in the league. His return to Denver will almost certainly be primarily as a mentor to all of the young guards on the Nuggets roster. However, adding Miller to the roster means that the Nuggets are down to just two open roster spot for three players on non-guaranteed deals - Joffrey Lauvergne, Jakarr Sampson, and Axel Toupane - and one player in Juancho Hernangomez who may spend another year in Europe before joining the team. Without a trade between now and the start of the season, it is very likely that Axel and Jakkar will be released from the team.
The signing still leaves the Nuggets well below the salary cap floor. In short, the Nuggets have money that they must spend in order to meet the league's minimum requirements. The Nuggets have until the end of the 2017 season to reach the floor so it is entirely likely that, barring a major trade, they will start the season below the floor.
Miller's signing should not encumber the team's flexibility in any way for the upcoming season or for the 2017-18 NBA season. The Nuggets have positioned themselves to have a lot of cap flexibility after the 2017-18 NBA season when Darrell Arthur, Wilson Chandler, Danilo Gallinari, and Will Barton, and Jameer Nelson will all be free agents. This signing fits right with that timeline.