You'd have hoped that clubs & agents would pull them to one side at 18, just before they sign their 1st big contract and explain how the real world works. That it's not all watches, whips, boats & hoes, and that they're a long time retired and to pick your friends & spouse carefully. Never confuse luxury expenditures with necessities and also avoid anything that has 'bespoke' or 'customized' in the title.
Live on 1/5th of your net income and invest the rest, in traditional investment classes and don't touch them. It might mean that you can't live like a baller, or a shot caller, or have twenty inch rims on the impala, but it will mean that for every year you play, you are banking 5 years of retirement living at roughly the same level, with a bit of wriggle room for your latter years. When you retire after a 15 year career, there'll be no noticeable difference to your living standard. Better a little caution than a great regret.