Although they reluctantly allowed him, the Dallas Mavericks weren’t keen on Dirk Nowitzki playing international basketball in the summer.

The Mavs would rather have seen Nowitzki rest in the off-season. Plus, if Nowitzki would have been injured, the medical financial burden would have fallen in their laps.

But international basketball was a ritual for Nowitzki in his early years with the Mavs. Playing for the German National Team was a source of pride, and continued a sort of a family tradition started when his mother, Helga, played for the national team in 1966.

Nowitzki is the first to admit that international basketball was critical in transforming him into a dominant NBA player.

In the late 1990ss and early 2000s, Mavs forward Michael Finley and point guard Steve Nash were the known qualities and the team’s star attractions. The unknown was Nowitzki.

“I played international ball, which usually helped me get better in the summer and put me in a position where I could be the man and demand the ball and then make decisions,” Nowitzki said. “Whereas in the league it was Steve and Mike who handled a lot of the ball, whereas in international ball I was the man and I was able to get the ball a lot and I think that helped me grow over the summers.”

That growth has put Nowitzki on the doorstep of an NBA milestone.

Entering Sunday’s 7:30 game against Oklahoma City at American Airlines Center, Nowitzki is 38 points away from becoming the sixth NBA player with 30,000 career points, joining Kareem Abdul-Jabbar (38,387), Karl Malone (36,928), Kobe Bryant (33,643), Michael Jordan (32,292) and Wilt Chamberlain (31,419).

Nowitzki joined the Mavs in a 1998 draft-day trade with the Milwaukee Bucks. Shortly after Mark Cuban bought the Mavs from Ross Perot Jr. on Jan. 4, 2000, the new owner began to engage in shooting contest with Nowitzki.

“I’d go out and shoot before the games and I’d shoot on the practice court, and I’d go down there and shoot knowing when Dirk would come out here,” Cuban said. “And he’d always do the same thing.

“He would walk out and say: ‘Whose house is it? Whose house is it?’ I’m like, it’s my [expletive] house, Dirk.’ ”

Cuban gladly acknowledges, “It’s Dirk’s house now.”

In the summer of 2004 things changed for the Mavericks, and Nowitzki.

Cuban didn’t match a free-agent offer for Nash by the Phoenix Suns, leaving the Mavericks without any compensation for a player who would win the next two league MVP awards. That left the team’s focus on Nowitzki, who was still smarting from losing his close friend Nash.

“[Nowitzki] took it upon himself to be that [go-to] guy,” Cuban said. “As much as losing Nash is probably my biggest mistake in owning the Mavs, I think it also helped Dirk in a lot of respects to just take on that responsibility and not defer.

“When Nash was gone, there was no doubt [who was the man].”

Nowitzki’s play in international basketball was his bread-and-butter, the place he laid the foundation for his game.

“I barely took any time off in the summer,” Nowitzki said. “I always tried to add something and get better from year one to year two, and the same from any other year.

“I played the summer league my first couple of years.”

Nowitzki was a basketball junkie and his fix, his safe haven, was where he felt most comfortable – in the gym.

Some day soon Nowitzki will join the 30,000 Club. But that’s not his primary focus. He has an eye on reaching the postseason for the 16th time in 17 seasons. With 21 games left, the Mavs (25-36) have a chance, and he wants to help get them there.

“I just want to focus on the next game,” said Nowitzki, who then seemed to realize what he’s about to achieve. “Actually, only five guys have [scored at least 30,000 points] in this league, so it’s an amazing accomplishment. I’m sure I’ll cherish it for the rest of my life.

“But as of now I’m trying to win games. I’m trying to compete and I’m trying to focus on the next shot.”