A glittering future looked assured for the 21-year-old after he won the TV reality show 'Football's Next Star' three years ago.
That success earned him an 18-month stint with Inter Milan, managed by Jose Mourinho, but the breakthrough at the San Siro failed to materialise and he returned home to England.
After spells in non-league football with Ebbsfleet and Welling, Inverness boss Terry Butcher offered him the chance of full-time football with a 12-month contract at the Caledonian Stadium.
And Greenhalgh, who moved to the SPL with fellow non-league new recruits James Vincent and Danny Williams, is keen to prove he can cut it at a higher level.
"I'll always have that 'Inter Milan thing' hanging on my back but I don't see it like that," he told Sky Sports News.
"I have got a good move here to Inverness, it's a massive opportunity and it's something I can push on with from now on."