Dirk Nowitzki is a free agent ... but the 40-year-old legend tells TMZ Sports when it comes to the NBA, it's "Mavs for life."
Dirk and the Dallas Mavericks have already mutually agreed to opt out of Nowitzki's contract -- which included a $5 million option.
The team is expected to sign a new, cheaper deal with Dirk -- unless he decided to explore other NBA options.
But, when we spoke with Dirk on the way out of Craig's in West Hollywood over the weekend -- he seemingly shut down all other teams .