The 20-year-old collapsed during a match against Werder Bremen after suffering from cardiac arrhythmia and was subsequently airlifted from the stadium before being placed in intensive care.
In a club statement issued on Monday, Ajax have issued a positive update on Nouri's condition, but have warned about making premature forecasts for his long-term recovery.
"Appie's heart is functioning normal and appears to be undamaged," began a statement shared on the Dutch giants' @AFCAjax_EN Twitter handle.
"It is however too soon to say anything about his recovery, as his brain function cannot be tested properly as long as he is kept asleep."
The midfielder, who made 15 appearances for Ajax last term, had received CPR on the field.
"Thanks to everyone for their support," Ajax had said in an earlier statement on Saturday. "We will keep you informed.
"For now: stay strong Appie!"