Former New York Jets quarterback Mark Sanchez and other professional athletes were cheated out of millions of dollars in a Ponzi-like scheme orchestrated by an investment adviser who appealed to their Christian faith.

Mr. Sanchez, Jake Peavy and Roy Oswalt, were defrauded out of about $30 million, according to a recently unsealed U.S. Securities and Exchange Commission lawsuit in Dallas federal court. The athletes all used the same broker, Ash Narayan, formerly of RGT Capital Management. The adviser gained their trust through religion and their interest in charitable works, the SEC said.

Mr. Narayan concealed multiple conflicts of interest from investors, the SEC said in its lawsuit against him. He directed the athletes’ cash to The Ticket Reserve Inc., which allows fans to reserve face-value tickets to sporting events where the teams have yet to be determined, the SEC said. He was on the company’s board of directors, owned more than 3 million shares and was its primary fundraiser — raising more than 90% of the company’s investment capital, the agency said.

Nick Sanchez, Mark’s brother and attorney, didn’t have an immediate comment. He’s currently with the Denver Broncos.

All three athletes sought low-risk, conservative investment strategies, the SEC said. Mr. Narayan ignored their requests and instead invested in TTR even as the company’s financial conditions were in distress. TTR’s chief executive officer wrote to Mr. Narayan in a May 2014 email that “To be sure our revenue sucks. Our balance sheet is a disaster.”

The case is Securities and Exchange Commission v. Ash Narayan, 16-cv-1417, U.S. District Court, Norther District of Texas (Dallas).