Cahill was expected to miss the rest of the season after being diagnoed with a blood clot in his left arm in February.
“He has trained ever so well, to a very high standard of which I have come to expect of him. I have been delighted,” said Coyle.
“Saturday might be too soon for him but he is continuing in the right direction.
“That is a tremendous boost for Gary, the club and I would suggest England.
“It is up to him once he is back in a Bolton shirt to show his qualities and take it from there.”