Di Santo, 20, confirmed his progress by netting for Blackburn in the 3-2 derby victory against Burnley at Ewood Park.
Allardyce believes their league rivals will require the Argentinian's services with a number of players away on African Nations Cup duty.
Chelsea are not in a position to go into the market as things stand either because of Fifa's transfer ban, which they intend to appeal against.
But Di Santo said: "I need to improve and gain experience. I need to play games and score goals. If I go back to Chelsea I will try my best but, if I stay here, I will continue my education.
“It is good for me being at Blackburn. I am very happy to be here because the manager has given me the opportunity to play. That has given me the opportunity to improve and gain experience and I hope to get better and better over the next few games."
On the possibility of Di Santo staying, Allardyce said: "I do not think that there is any real chance of that.
"There is a transfer ban on Chelsea and with the African Nations coming up they will probably need him.
"Di Santo was terrific - he is a young man learning his trade. He has finally got a chance to start some games and he has grasped it.
"What pleased me was the lay-off for Dunny's goal. He will take confidence as well from his first goal in the Premier League. If he can continue to play like this it will be good for us and Chelsea."