Inter midfielder Eriksen collapsed in the first half of the Euro 2020 match in Copenhagen with no other player around him.
He was given CPR by medics and the fixture was originally suspended, but once Eriksen was confirmed to be "awake" the game resumed just under two hours later, Finland going on to win 1-0.
The Danish Football Union (DBU) provided an update on Sunday, confirming that he had suffered a cardiac arrest but his condition was stable pending further examinations.
Team doctor Morten Boesen detailed how he could initially feel a pulse when he arrived at Eriksen's side, but that "suddenly changed" and meant CPR was necessary.
The medical team and Denmark captain Simon Kjaer were widely praised for their respective roles, with the centre-back quickly placing Eriksen in the recovery position.
And, speaking through his agent to Gazzetta dello Sport, Eriksen relayed a brief message of thanks as he now sets about learning why it happened.
He said: "Thank you, I won't give up. I feel better now, but I want to understand what happened. I want to say thank you all for what you did for me."
Denmark is next due to be in action on Thursday against Belgium.