The NFL let players break a rule this weekend. About shoes. For a good cause.

In 2013, Brandon Marshall of the Chicago Bears took the field wearing bright green cleats — and was fined $10,500 for it.

He stood by his decision because he knew how important those green kicks could be to people watching the game. Two years prior, Marshall was diagnosed with borderline personality disorder. He decided that during the Bears' Oct. 10 game that year — a nationally televised game against the New York Giants — he'd wear green cleats to draw attention to Mental Health Awareness Week.

$10,500 is the fine the league charged him with for violating its strict dress code.

"Football is my platform not my purpose," he tweeted in response to notice of his fine. "This fine is nothing compared to the conversation started & awareness raised."

The first weekend in December 2016, you may have noticed huddles looking less like this:

And instead, a lot more ... colorful:

So what gives? Did every player get served a $10,500 fine for their colorful cause-worthy footwear?

On one hand, if players can use their gigantic platform and audience of millions to draw attention to a good cause, that's a good thing, right? On the other, the point of uniforms is to be, well, uniform with everyone else on your team.

It's actually part of a compromise worked out by the NFL and players like Marshall who want to draw attention to good causes. It's called #MyCauseMyCleats. For one week of the season, the league is giving players the chance to sidestep the league's uniform policy to wear customized cleats repping the cause of their choice.

After the games are over, these one-of-a-kind pieces of field-worn footwear are being auctioned off — with 100% of the proceeds going to the players' charities of choice.

Here are some of the super creative designs and the charities that inspired them:

1. Chris Conley of the Kansas City Chiefs supports Enduring Hearts, an organization aligned with the American Heart Association.

2. Eric Berry, also of the Chiefs, supports raising Hodgkin’s lymphoma awareness.

3. Jimmy Smith of the Baltimore Ravens sports cleats with the motto "Sideline Racism" for the Ross Initiative in Sports for Equality (RISE).

4. Mark Ingram of the New Orleans Saints shows support for the Mark Ingram Foundation, an organization for children with incarcerated parents.

5. Antonio Brown of the Pittsburgh Steelers reps Big Brothers Big Sisters cleats.

6. Marcell Dareus of the Buffalo Bills gives the American Heart Association his backing.

7. Steve Smith of the Baltimore Ravens takes a stand against domestic violence.

8. Morgan Cox, also of the Ravens, supports the Colleen's Dream Foundation, an ovarian cancer research organization.

9. Travis Kelce of the Kansas City Chiefs supports his 87 and Running charity for disadvantaged youth.

10. Rex Burkhead of the Cincinnati Bengals wears these cleats for the Team Jack Foundation against child cancer.

11. Johnny Hekker of the Los Angeles Rams reps Waterboys, an organization dedicated to providing clean water to people in East Africa.

12. Vance McDonald of the San Francisco 49ers supports Convoy of Hope, an anti-poverty organization.

13. Matt Ryan of the Atlanta Falcons honors Children's Healthcare of Atlanta with his footwear.

14. Von Miller of the Denver Broncos throws his support behind his charitable organization Von's Vision, which brings eye care to low-income children.

15. Golden Tate of the Detroit Lions gave a shout out to his Golden Future Foundation to supporting veterans.

16. Pierre Garçon of the Washington Redskins highlighted his Helping Hands Foundation for people in Haiti.

17. Russell Wilson of the Seattle Seahawks gave a boost to his Why Not You Foundation to support children.

18. Michael Thomas of the Miami Dolphins donned cleats during his pre-game ritual to call out police brutality.

19. David Johnson of the Arizona Cardinals took on bullying with his Stomp Out Bullying cleats.

20. DeAndre Hopkins of the Houston Texans used his footwear to call for an end to domestic violence.

21. Jason Pierre-Paul of the New York Giants drew attention to the Haiti Relief Fund.

22. Roman Harper of the New Orleans Saints demonstrated his commitment to children's education and mentorship with a bump to his Harper's Hope Foundation.

23. Derrick Johnson of the Kansas City Chiefs gave props to his Defend the Dream Foundation for low-income individuals.

24. Rodney McLeod of the Philadelphia Eagles helped out disadvantaged children with a shout-out to the Audience of One charity.

25. Shaq Lawson of the Buffalo Bills wanted to bring attention to cystic fibrosis with his shoes.

26. Julius Thomas of the Jacksonville Jaguars put a foot forward for Episcopal Children's Services.

27. Odell Beckham, Jr. of the New York Giants wore some cartoon-heavy cleats for the Make-A-Wish Foundation.

28. Jarvis Landry of the Miami Dolphins showed support for the Cystic Fibrosis Foundation.

29. And finally, Brandon Marshall, now playing for the New York Jets, laced up his green cleats to again bring some much-needed attention to mental health awareness — this time without a fine.

Marshall's shoe-based activism was cool when he got fined, but it's even better when the money raised goes toward helping his cause.

Hundreds of players across the league participated, teaming up with artists to craft the perfect messages in support of their cause of choice, and the results, as you can see, are phenomenal.

On the NFL's website, players shared personal stories about why they're passionate about the causes they've chosen to support. For some, it's a throwback to their own childhood or an illness facing a family member; for others, it's just about giving back to those in need. Creative approaches to bringing attention to positive causes is always a big win.

For a look at all the cleats, check out NFL.com.