Khalifa says the security guards then clutched their arms and ushered them out. No one would tell them what was going on.
"Then they started asking us what mosques do you attend? How regularly do you go?," Khalifa remembers.
Later, FBI agents told Khalifa that they were reacting to a tip: that someone saw the men crouching near an air vent at the stadium. He admitted they were on their knees to pray.
"You know we've prayed in front of people before and it was never a problem. So we didn't think about it twice. It something we do everyday, five times a day, everyday. Anywhere we are," Khalifa says.
George Zoffinger is president of the complex where the Giants play. He says his staff handled the situation correctly and is sensitive to cultural diversity.
But, he adds, "Any time that we receive any kind of indication from our patrons or from our security staff that they're concerned about something we make sure that we look into it."
After all, the New York City skyline, a constant reminder of 9/11, is in plain view of Giants Stadium. Security is never far from anyone's mind.
"I know that in our everyday lives, you and I and everybody else, we are so cognizant of the fact that if you do see something unusual that you should report it. And I think that has been so ingrained into all of our thought processes," Zoffinger explains.
But does "praying while Muslim" qualify as unusual?
"One person actually looked me in the eye and said, 'You know, now I feel safe.' I'm like, 'From what? Just watchin' a football game,'" Khalifa says with a laugh.
Many Muslims say they're used to getting the evil eye. In one survey of young Muslims, 70 percent said they noticed significant hostility toward Muslims in the general American public.
And there are those who believe it's not unwarranted.
Daniel Pipes is the director of the Middle East Forum, and makes no apologies for taking a hard line. "I think there should be a focus on Muslims," Pipes says.
Pipes points out all 19 hijackers on September 11th were Muslims. And four years later we're still debating whether protecting the country or protecting civil liberties is more important.
"There has to be a balance between the two. It's important to focus in on the real threat. It does no one any good to pretend that threat is other than what it really is," Pipes says.
And he says the "real" threat to the United States is radical Islamic terrorism.
"Are we going to protect ourselves from this or not?" Pipes asks. "The people who are going to do this who will in the future engag