Sam Champion called it “the biggest day in our musical history” — a show that had been promoted for weeks, in a location kept secret. But U2′s performance on Good Morning America last Friday, the group’s first live morning show performance, did not do much for GMA’s ratings.

The show was GMA’s least-viewed of the week in Total Viewers with 4.594 million. In fact, the #1 “Today” show topped #2 “Good Morning America” by 1.417 million Total Viewers Friday, the widest gap of the week.

In younger viewers GMA fared better, averaging 2.18 million in the A25-54 demo, besting their previous two Fridays.

And in Total Viewers, GMA had its best week since February 25, 2008. Tuesday’s GMA (5.408m Total Viewers) was helped by Monday night’s finale of “The Bachelor.”

• Earlier on TVNewser: Even With a Week of U2, ‘Nightline’ Still Tops Dave