A strong Reds' team secured a 4-1 victory over an Irish League XI thanks to goals from Patrice Evra, Ashley Young (2) and Wayne Rooney.
A sell-out crowd at Windsor Park, virtually all supporting Sir Alex's men, were clearly delighted with the result on a night when everyone came together to pay tribute to one man.
"All the lads are really proud to be involved in a night like this for someone who is a hero both on and off the pitch," Giggs told MUTV. "The testimonial is just reward for a great career and a great life.
"It's always nice to come back to Northern Ireland. The fans over here are unbelievably loyal.
"There was a full house tonight even after the disappointment of Sunday and they cheered us on all night. We always get a great welcome over here and we know how much the fans over here love the club.
"The standard [of the game] was pretty decent," added Giggs. "There were plenty of goals and plenty of good goals too. Hopefully we sent the crowd home happy."