By Simon Evans

MIAMI (Reuters) - German Dirk Nowitzki was hailed as one of the all-time greats after he crowned his 13 years in the NBA with a first championship ring following the Dallas Mavericks 4-2 series win over the Miami Heat.

Named Most Valuable Player (MVP) of the Finals, Nowitzki's outstanding performances throughout the playoffs, with six 30-plus scoring games, were crucial to Dallas' success as they gained revenge for their loss to Miami in the 2006 season.

"Dirk Nowitzki is simply one of the all time greats. And he was when we played him in 2006," Miami coach Erik Spoelstra told reporters.

"His game has continued to elevate in his 30s. That's a remarkable thing. I think that's a great lesson for NBA players.

"You can still improve as you get older and add more skills and dimensions to your game. He is probably one of the most indefensible players in this league, because of his skill set, his shooting and his size. And now he's seen every single coverage he can possibly see."

Nowitzki's coach Rick Carlisle said he was sure that this season had established the German as one of the best ever in the league.

"I don't think there's any doubt after this series that Dirk has certainly earned the clout of being one of the all time great players.

"His versatility, how he's done it in the clutch. He goes 1 for 12 in the first half, and then in the second half he was just absolute money," Carlisle said in reference to the German's performance in Game Six on Sunday.

Nowitzki averaged 26.0 points per game in the finals and was incredibly accurate from the free throw line, missing just one of 44 attempts to banish memories of the loss to Miami five years ago and finally win a ring.

"This is what I obviously played for the last couple of years," Nowitzki told reporters.

"I think when you come in to this league you want to establish yourself. All these All Star Games and all those things are nice but when you get to a certain age, you've basically seen it all, and all you play for is for that ring.

"If you're in this league for 13 years of just battling and playoffs for basically the last 10 or 11 years, and always coming up a little short, then that is why this is extra special," said the seven foot Nowitzki.

"If I would have won one early in my career, maybe I would have never put all the work and the time in that I have over the last 13 years. So this feels amazing," he said.

"I think he's played awesome. Obviously Dirk, five years ago, it burned in him. He learned from that experience. Even though he was 1 for 12 in the first half, he came out and made big shots for his team. He kept being aggressive, he kept shooting.

"So there's no question he's been a great individual player and now that he's a champion, it goes without saying, what it means for his career."

(Editing by Patrick Johnston)