17. John Elway
There are a lot of hedge fund managers out there ready to sink their claws into NFL players. Even Elway fell foul of this in his days as a younger businessman. The Denver Broncos icon poured millions into a Ponzi scheme back in the day but lost almost all of his investment because it fell apart. Elway and his partner were two of about 65 people who invested in Sean Muller’s shady scam.

Of course, Elway is doing very well for himself these days, but he also missed a massive investment opportunity back in 1998. Broncos owner Pat Bowlen offered him a 10% stake for $15 million. He turned it down but it must be painful to look back because it would be worth about $400 million today. NFL players, both present and past, need to be so careful who they give their money to.