The Wales international central defender joins on a contract until 2025 and will wear the number 14 shirt.
"It hasn't really hit me yet," said Rodon. “It's a massive honour. This is a massive Club, and I can't wait to get started... coming from my boyhood club to this position is only something I could have dreamed of. It's been a great week and to finish it off in this way is a dream come true.
“I always loved playing football, and here I am. It's what every kid wants to do. I used to go to the park and play football every day, you just grow to love it."
A year before he signed that first professional contract, 2014, a certain Ben Davies left the Swans to join Spurs. Six years down the line, they are club and international team-mates – they played together in those three Wales games last week.
“It's a great story and to join Ben here now is even better for me," said Joe. “Ben and Gareth are two massive players for Wales, and hopefully they can help me settle in quickly and make me feel even more welcome. Yes, that was a big part for me. Hopefully, it all goes perfectly.
"As everyone knows, Jose Mourinho is one of the biggest managers in the world, and all I can do is be excited, learn every day and hopefully take it all on board.
“I'm not looking too far, just to take each day as it comes, hopefully improve and become a better player, and take it from there."