The Spaniard suffered what he said was the biggest crash of his career after clipping the back of Esteban Gutierrez's Haas car at Albert Park last weekend.

He speared off the track into the wall before being pitched into a barrel roll and ending up upside down against the barriers.

Honda flew his engine back to Japan for investigations to determine the extent of damage, and the initial indications seem far from promising.

While that work continues, it has been decided he will take his second power unit of the campaign for the next race.

A Honda spokeswoman said: "There is a high probability that most of the power unit components have been damaged by Fernando's accident in Melbourne.

"It is still too early to tell if there are any salvageable parts. Therefore, we will be using a new power unit for the Bahrain GP."

Electing to give Alonso a fresh power unit now means that more time can be spent properly evaluating the damaged Australian unit.