"I've seen the record with short-term goals of going back to the A-League and the destruction that it's had on top players' careers who have come back to finish there.
"Del Piero was one of the biggest things to ever happen to the game, but also the worst because it wasn't capitalised on."
Behind the scenes FFA are incredulous and bewildered at the attack from such a prominent member of the Socceroos.
At least publicly, Gallop was unemotional.
He disputed some of Cahill's remarks, saying FFA had a "clear 20-year vision" along with a shorter-term strategy that will provide growth and financial stability.
The FFA boss also said numerous parties tried to sign the Australian forward after learning of his availability, but could simply not afford the fee he wanted.
"We contacted Tim and his advisers immediately when we heard he was not going to be part of Shanghai any longer," Gallop said.
"A number of our clubs also contacted him immediately. I personally was in contact with him. "He made it clear immediately that we couldn't meet his needs."
Cahill also criticised the fact that the Socceroos have gone three years without a major sponsor.
"We've played in three World Cups and we don't really have anything to show for it," he said.
"Every time I go back it's mayhem and you don't understand how that makes me feel, but at the moment the game is in a bit of a rut where it's caught in a crossroads."
-AAP