It was the week before the start of this year's National Basketball Association season.

Mark Cuban, the billionaire owner of the Dallas Mavericks walked onto a basketball court before the game began and a loud applause greeted him as he took his courtside seat.

But Cuban was not in Dallas, Texas. He was in Shenzhen, China for a preseason game where the Mavericks competed against the Philadelphia 76ers in front of tens of thousands of Chinese fans.

Here in the world's most populous country, basketball is a massive business and the NBA's fan base has grown.

It was the first time the two teams were playing in China, but it was the 26th game to take place in the country, since the NBA began bringing games there in 2004.

"If there's a second center of the basketball universe, it's China," Scott O'Neil, CEO of the 76ers told CNBC.

The NBA has grown to become China's most popular sports league. It's formed partnerships with some of the country's biggest tech companies and opened NBA stores and new experience concept stores inside malls.

According to the league, more than 300 million people in China play basketball. Meanwhile, the NBA is the most followed sports league on social media with more than 150 million followers.

"The world is getting flatter and flatter. You can interchange someone from Philadelphia and Shanghai, you can rotate them, and no one will know the difference," O'Neil said. "We listen to the same music, we watch the same basketball, we follow the same trends, it's pretty incredible."

The NBA's history in China dates back to the late 1980s when its commissioner at that time, David Stern, met with China's state run television network CCTV to get games on air.

By 1994, all the NBA finals were shown live in China.