Patriots owner Robert Kraft is worth $6.6 billion and counting. Like many owners of American sports franchises, he made his money outside of sports, then bought in as a fully-formed billionaire. He became famous for his role with the Patriots, but he would’ve been a rich man with or without them.

It’s a pattern gone boilerplate since the ’70s, as the potentially huge leaps in profit attract wealthy investors looking to diversify. Once George Steinbrenner bought the New York Yankees for a paltry $10 million, turning it into a multi-billion dollar franchise, the face of sports ownership changed for good.

But Kraft is more than a billionaire looking for a safe investment. In recent years, he’s continued to leverage his experience in sports, quietly building an empire in uncharted territories.

How Robert Kraft became a billionaire

RELATED: A Breakdown of How Robert Kraft Pays the Patriots

According to a CNN profile on Kraft, he made his fortune in paper and packaging. That started in 1965 when he graduated from Harvard Business School and joined his father-in-law’s company. By 1968, he owned the majority of the company via a leveraged buyout.

The conglomerate that emerged became one of the leading paper multi-national corporations. Kraft expanded his holdings into the raw materials of his products, including wood pulp. It turned into a lucrative, all-encompassing project that gave him the ability to move into other spaces — including the one he’s most famous for.

Why Kraft took the risk of jumping into sports

RELATED: Robert Kraft May Not Have Saved Tom Brady, but He May Be Saving Lives

When Kraft took the $172 million plunge to realize his lifelong dream of owning the Patriots, he broke several personal rules of business to do so. After a stint running a low-profit tennis team, he took note that he could’ve made a mint if he owned the stadium. That would give him access to profits from concessions and ticket sales.

To pull it off, he had to make a move to buy land around the Patriots’ old Foxborough stadium. That left him holding an investment with little purpose, given that he lost a 1985 bid on the team itself. The risk eventually paid off, when he got the opportunity to buy the stadium itself from the failing organization in 1988.

Finally, he was able to buy the team in 1994, as Forbes reports, allowing him to sigh a breath of relief. This wasn’t how Kraft normally did business. But it gave him a new model that he would follow up on over a decade later.

Kraft’s big bets on growing new spaces in pro sports

“We like to always try to be involved in a lot of new, cutting-edge things,” Kraft told ESPN in 2018. “Wherever the market is going, we like to try to get there a little bit ahead.” His sports-related investments since the Patriots certainly point to a willingness to stake out new territory, rather than sticking to more stable revenue streams.

His first move following that model was becoming a founding owner in MLS. He bought the New England Revolution in 1996, according to the Kraft Group website. The group still runs the team today.

NBC News reports that in 2016, the Kraft Group was one of the major investors involved with WME’s buyout of UFC. The sport was rising out of a tough period of being demonized as dangerous. Kraft took the risk nonetheless, betting on further rapid growth as lucrative deals such as broadcasting on ESPN showed signs of it becoming permanently mainstream.

And most recently, Kraft was the first owner on board for the biggest esports league launch yet. He partnered with Activision-Blizzard to run a competitive squad for their futuristic competitive shooter, Overwatch. ESPN reports that Kraft’s vote of confidence led to a huge leap in investor interest, solidifying the league’s status as a potentially huge profit center.