My guess... A bunch of air.
Follow-up...
The ball did likely contain an NFC chip, placed there by the manufacturer. https://www.adidas.com/us/b/soccer/telstar_18/faq.html
My guess... A bunch of air.
Follow-up...
The ball did likely contain an NFC chip, placed there by the manufacturer.
https://www.adidas.com/us/b/soccer/telstar_18/faq.html