The San Francisco Giants have sold a reported 10% stake in the team to private equity firm Sixth Street.

The team confirmed the deal Tuesday but not the amount of the investment, which was first reported Monday by The New York Times.

Sportico places the value of the franchise and its team-related holdings at $4.2 billion.

Sixth Street's investment, reportedly approved by Major League Baseball on Monday, will go toward upgrades to Oracle Park and the Giants' training facilities in Scottsdale, Arizona, as well as Mission Rock, the team's real estate development project located across McCovey Cove from the ballpark.

Giants president and CEO Larry Baer called it the "first significant investment in three decades" and said the money would not be spent on players.

"This is not about a stockpile for the next Aaron Judge," Baer told The New York Times. "This is about improvements to the ballpark, making big bets on San Francisco and the community around us, and having the firepower to take us into the next generation."

Sixth Street is the primary owner of National Women's Soccer League franchise Bay FC. It also has investments in the NBA's San Antonio Spurs and Spanish soccer powers Real Madrid and FC Barcelona.

"We believe in the future of San Francisco, and our sports franchises like the Giants are critical ambassadors for our city of innovation, showcasing to the world what's only made possible here," Sixth Street co-founder and CEO Alan Waxman said in the news release. "We believe in Larry and the leadership team's vision for this exciting new era, and we're proud to be partnering with them as they execute the next chapter of San Francisco Giants success."

Founded in 2009 and based in San Francisco, Sixth Street has assets totaling $100 billion.