Ball said he believes Foster "used his access to my business and personal finances to enrich himself," with roughly $1.5 million from Ball's accounts being unaccounted for.
Foster has a 16.3 percent ownership stake in Big Baller Brand and has served as the business manager of the Ball family's companies since 2014.
Lonzo's financial adviser, Humble Lukanga of Life Line Financial Group, stated in an October email that the taxes of both Lonzo and Big Baller Brand couldn't be completed in a timely manner due to the missing $1.5 million.
Concerned about Foster, Lonzo reportedly deferred to his father to handle the matter, sources close to the family told ESPN.
"I've always believed in the best in people. Regretfully, I put my complete trust in Alan Foster to manage my son's business affairs," LaVar Ball said in a statement to ESPN after reportedly reviewing warnings and documents from Lukanga this week. "At the end of the day, family comes first, and I support Zo wholeheartedly. Together, we will make this right."
Federal court records obtained by ESPN show Foster was sentenced to more than seven years in prison back in 2002 after pleading guilty to one count of mail fraud and two counts of money laundering.
Lonzo had been unaware of Foster's transgressions when it was brought to his attention during an interview with ESPN several weeks ago. This led to the 21-year-old reportedly asking questions to those close to him about Foster's past.
Harrison Gaines, Lonzo's agent, published a statement Friday evening concerning ESPN's story on Foster:
"This is a stunning development and very unfortunate situation for all involved," Gaines said. "Due to the Ball family's business structure, my interactions with Alan Foster were very limited.
"I had one responsibility: manage the employment of Lonzo with the Los Angeles Lakers and guide his younger brothers in the pursuit of their basketball aspirations. At best, I was on the periphery of the rest of the Ball family businesses.
"This is a cautionary tale and I'm glad Foster's actions have been discovered," Gaines continued. "Lonzo has now empowered me to take a more active role in his career. I look forward to continuing as his agent and providing guidance that will support his growth as a person and player."