The friendly marked the opening of their new stadium which has been designed by Frank Whittle Partnership of Preston
FC United are the largest fan-owned club in the country with over 4,000 shareholders and Karl Marginson, the FC United manager since the club was established in 2005, summed up the tone of the evening.
"We have gone from no balls to playing Benfica in 10 years," he wrote in his programme notes for the fixture.
"This club is much more than football, and I'm not being a pompous idiot in saying that. Without the fans there is no team, simple as that."
The new ground is in Moston, North Manchester about 2 miles from the Etihad and not much further from Oldham's Boundary Park ground.