Delfouneso will start against Fulham on Saturday due to injuries on Emile Heskey and John Carew and that Gabriel Agbonlahor is still recovering after a groin operation.
“It is an ideal opportunity for the young Nathan to step up. He will definitely be the main striker,” said Villa boss Gerard Houllier.
Delfouneso have made 14 appearances as a substitute for Villa during the past three seasons.