Neill's decision to join the Sky Blues over Melbourne Heart after negotiations reached an advanced stage with the Victorian club, prompted an angry reaction from Heart's fans.
"I'm not really bothered about what the Heart fans will do, and I can certainly say Lucas won't be too bothered either," Farina said.
"It's a game of football and they pay good money to see it, so they can do whatever they want."
Farina said Neill's signing for the rest of the season had "certainly changed the feel around the place here."
The morale boost was heightened when Italian super star Alessandro Del Piero signed on for another year.
"I think it rubs off in some sort of way, to know that there's stability and who's going to be here," Farina said.
"But the most important thing is the game on Sunday - if we turn up and we're competitive."
Farina's biggest task in the meantime is a welcome new one - juggling a full squad for the first time, with the addition of Neill coinciding with the return of Joel Griffiths, Brett Emerton and Ali Abbas from suspensions.
Farina was tight-lipped about the make up of his team but Neill seems set to join Brazilian Tiago Calvano in the central defence.