This is quite obvious. Many athletes advertise various brands, products, services. And these companies that they advertise have been using cryptocurrencies for a long time and even release their own. And besides, transactions of large loans of money are easier to do with cryptocurrency, and this is a fact that many rich people and various companies resort to.

guess, he is not the first one who accepted btc or in some way accepted crypto as payment. been long time that there are known sports personalities that are into crypto. just quick search and you will find one. i believe there are more of them

15 professional athletes who are into crypto

but the more personalities, the better for crypto industry. because they have different sets of followers and supporters. and those supporters in some way will check the activities of their idols and who knows, it will pave the way for some to check out crypto or btc. which is good for crypto adoption

For bitcoin not for crypto.
Sadly the cryptocurrencies still have a long way to go to start being taken seriously and not just be referred to pump and dump schemes. The more bitcoin grows the less attention will be given to cryptocurrencies too because all the attention will go to bitcoin.

I also often see famous sports players using Bitcoin such as Lionel Messi, Didier Drogba, Ronaldinho etc.

Example:
15 Professional Athletes who are into crypto

It can be said that in the world of sports, football, boxing, basketball, tennis, Bitcoin is familiar to them, for example what happened to Pacquaio, he has created his own type of crypto that is ready to be marketed called PAC coin.

My opinion is in the next 5-10 years Bitcoin will become one of the digital currencies that can be accepted as a salary for sports athletes around the world, that's my thought.

Soon it will be recognized as an International digital currency which others country would accept bitcoin as what it is.

That's good news, really. As BTC will now be trusted by many other people supporting sports. As they see it as a probable source of income and see many known people to actually earn from it is a good step for the crypto community. Though, lets be real, this would mean bigger demands for btc that means BTC will soar higher this year. Might just hodl my coins a lil' longer.

Bitcoin is already big in sports, the bookings are already using BTC and some other cryptocurrency. Adopting BTC and cryptocurrency in FIFA is going to make it better and maybe sooner the bad image of BTC painted by media will change.

Adoption has yet to make it because the media has not really pointed out to regular people that they can actually buy it as investment or currency itself.

And just to add a little more information since we're talking about sports, in the esports scene, more pros are actually advertising cryptocurrency through the betting sites that they are endorsing, whether it be Bitcoin or ETH, they not only buy and sell crypto but they also endorse it to their audience, mostly these youtubers/pro players actually are the ones who highly endorse cryptocurrency and at the same time buy it for themselves to use it on the betting sites, the game I'm talking about here as well is CSGO