(CNN) Last month, the Detroit Lions made their 29-year-old franchise quarterback Matthew Stafford the best-paid player in NFL history, inking a $135 million contract that included a $50 million signing bonus.

Until recently, bets might have been taken as to just how long that money would last him.

Not anymore.

While pro athletes have been mismanaging their finances for decades, a combination of the realization of health risks and greater financial savvy have led many of Stafford's NFL contemporaries to reverse that trend.

"I saved (my first pay check)," says retired 11-year veteran Osi Umenyiora, who won two Super Bowls with the New York Giants after being drafted in 2003.

"I was really smart about my money, because the knowledge had started to come out (that) a lot of players were going broke."

During the tail end of his career, Umenyiora, who was born in London and raised in Nigeria, launched a financial planning company for African-born NFL players with the help of his brother.

"I was given a lot of advice from former players," Umenyiora tells CNN, noting that his one big purchase as a rookie was the house he lived in, calling it a "win-win situation" as an investment.

"The NFL really tried to harp on you not going broke because they don't want to see that statistic."

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The dreaded 78%

"That statistic" Umenyiora refers to was spawned from a 2009 Sports Illustrated article that claimed 78% of NFL players were penniless only a few years out of retirement.

The 2012 ESPN documentary Broke , which chronicled the financial ruin of several high-profile athletes, only reinforced that idea.

Tragically, the most famous member of that class, Hall of Famer Junior Seau, committed suicide and was later diagnosed with CTE, a degenerative disease caused by head injuries. Seau, a linebacker, played 20 NFL seasons and was known for his vicious hits.

Thirty-five year-old Umenyiora says he had his own financial adviser out of college who assisted him, and cites star teammate Michael Strahan -- who has gone on to stardom as a morning show host -- as someone who offered advise on how to invest his money wisely.

But another of Umenyiora's teammates, Jack Brewer -- who had a far more typical NFL lifespan, appearing in just 40 games in four seasons -- is perhaps a better case study in the advancement of career planning within the league. (The average NFL career lasts just 3.3 years, according to the NFL Players Association.)

As an undrafted rookie, Brewer signed with the Minnesota Vikings and took his bonus check -- all $8,700 of it after taxes -- and invested it in an on-campus bar at the University of Minnesota, while purchasing a car to promote events.

During his playing career, the NFL introduced its Continuing Education Program , where it would reimburse active players for taking college classes in the offseason.

"No other league has a robust program like the NFL," Brewer says. "The NFL is by far the best, and gives the players the most resources when it comes to education."

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A new approach

Now running an investment firm in New York, Brewer took executive classes at Harvard and Wharton, and eventually finished his MBA from the University of Miami, all paid for by the NFL and the NFL Players Association, he says.

"A player in the National Football League today has no excuse for leaving the game and not having his education, no excuse for leaving the game not being prepared," he says. "The resources are there. They would have to choose to not use them."

Happy birthday to two of my fellow #Lions @iamsrice & @clintonportis #LionOrder #Love #Respect A post shared by Jack Brewer (@jackbrewerbsi) on Sep 1, 2017 at 6:33pm PDT

Brewer's company The Brewer Group, now works alongside the University of Miami in recruiting athletes to enroll in its business school. So far, he has mentored 80 former professional athletes who have completed their MBAs.

"If you go into NFL as if it's a stepping stone, and you want to use the access you get from the NFL to do great things, your finances are going to be fine," Brewer says.

Former Seattle Seahawks receiver Sidney Rice, who won a Super Bowl in 2014 and retired at 27 after sustaining multiple concussions, is an example of a player taken under Brewer's wing.

Rice completed his executive MBA at the University of Miami and owns a number of fast food and coffee franchises in the Seattle area, as well as a sports apparel company. Before retiring he had already invested in a string of Fresh Healthy Vending machines.

Twenty-nine-year-old Sergio Brown, who played in eight games for the Buffalo Bills last season, is another University of Miami MBA. Rather than try out for another team, the seven-year veteran called it quits in the offseason and signed with Google instead, as a digital advertising account manager.

"No doubt, there a lot more guys like Sergio Brown coming out," says Brewer, noting how the greater knowledge about head injuries has impacted players' decisions to change careers while still able to play.

"It's the awareness that's changing the game more than anything," he says. "Guys are going brain dead right now, guys are developing Alzheimer's early. When those are the realities of the game, you will probably approach things a little bit differently."

When asked to respond to Brewer's comment, the NFL said in statement: "The health and well-being of our players is our priority, and (we) offer numerous programs and benefits for former players."

It cited a number of league-driven initiatives, including a slew of health benefits for retirees, such a stipend of up to $5,250 per player for knee, hip or shoulder replacement surgery, monthly payments to players who have a mild or moderate neurocognitive impairment, and medical cover of up to $130,000 for those who suffer from dementia, ALS and Parkinson's disease

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Short careers, long foresight

Like Brown, who grew up in a rough part of Chicago, Brewer comes from a modest upbringing in Fort Worth, Texas. He says he understands the pitfalls of immediate wealth which can lead to bad planning.

"A lot of these guys come from poverty, and once they get a little bit of money they feel so indebted to their families and close friends that they want to take care of them," says Brewer.

"They don't want to leave them in the conditions they are living in while they advance. It's almost like you have a sense of guilt, and so that is a tough situation to deal with."

Brewer used to invest money on behalf of NFL players, but found the process "emotionally and physically draining."

"There is so much hand holding (which takes) so much time," he says. "You've got to deal with their parents, their families get involved ... it's a little bit overwhelming."

Instead, Brewer often gives free advice to athletes on how to handle their money, at least until their NFL pension kicks in.

Umenyiora, who lives in London and works as an NFL analyst for the BBC, is quick to point out he won't see a dime of his retirement fund until he turns 55. In order to qualify, a player must have played in at least three games in each of three seasons.

"There are 25, 30 years for most players before they can start collecting on that pension," he says. "So you still have to be really smart and wise about how you spend the money you earn, because, quite frankly, the career isn't that long."

Today's NFL players, it appears, are certainly getting the message.