Owners Mark Cuban believes Dirk Nowitzki can be elite for at least three more seasons. It's wishful thinking from Cuban. Nowitzki will be 35 in June and is wrapping up a 15th season that saw him fall off a cliff. Over the last four seasons, his points per game have declined from 25.0 to 23.0 to 21.6 to 16.4. He's also dealt with knee and back issues, leading to 29 games missed already this year.