Dirk Nowitzki is regarded as the best international player in NBA history. Only the sixth player to reach the 30,000-point milestone, Nowitzki believes one day Kristaps Porzingis will best him. The Mavericks’ 39-year-old legend called the 7-foot-3 Latvian “a walking mismatch.’’ “He plays a lot more defense than I ever have, I’ll tell you that,’’...