Tim Krul made a string of fine saves, former United defender Danny Simpson denied Javier Hernandez with a magnificent goalline clearance and the Mexican had an effort ruled out for offside deep into stoppage time.
"It was a fantastic performance by us and an incredible result," said Ferguson.
"I could see us scoring because we kept creating chances and the normal pattern of these 15-minute surges is that we create chances and we are okay.
"They put their bodies on the line. I give them credit for that.
"We absolutely slaughtered them but we just couldn't get the result.
"It is disappointing but if we play like that every week, I will be very happy."