Carrie Underwood 'Yesterday': Paul McCartney Approved Emmys Performance

Country singer Carrie Underwood said she was moved by Paul McCartney's approval to sing The Beatles' classic song "Yesterday" at Sunday's Emmy Awards.

She sang "Yesterday" in honor of the 50th anniversary of television milestones like The Beatles' appearance on "The Ed Sullivan Show" and coverage of the John F. Kennedy assassination.

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Underwood tweeted Sunday about the Beatles star reaching out to her before the performance.

The coolest thing about singing "Yesterday" on the #Emmys is the sweet letter I got from @PaulMcCartney giving me his blessing to sing it!

— Carrie Underwood (@carrieunderwood) September 23, 2013

The Los Angeles Times reported that Underwood's rendition of the song garnered 17,090 tweets per minute. The reviews of her performance were mixed.

This is an #Emmys where Jon Hamm lost for the sixth consecutive time and we had to sit through Carrie Underwood singing the Beatles.

— Eric Deggans (@Deggans) September 23, 2013

Carrie Underwood! aldc_official Simply stunning and so sweet! #dancemoms #abbysultimate http://t.co/MLFzrDhTIP

— Abby Lee Miller (@Abby_Lee_Miller) September 24, 2013

Just because the Beatles were great doesn't mean we should have to watch Carrie Underwood.

— Mike Birbiglia (@birbigs) September 23, 2013

Underwood also tweeted about meeting singing legend Elton John before the show.

The amazing @eltonjohndotcom just came to my dressing room to say hi...we talked for a bit. I think I can safely say we're best friends now!

— Carrie Underwood (@carrieunderwood) September 22, 2013

It was Underwood's second high profile performance in the past three weeks. The former "American Idol" winner introduced a new theme song for NBC's "Sunday Night Football" on Sept. 8, reported Rolling Stone.

"Yesterday," which was written by McCartney and John Lennon in 1965 and debuted on The Beatles' "Help!" album.

Underwood has sold 14 million albums worldwide since winning Season 4 of "American Idol" in 2005. The country singer has won five Grammy Awards and has scored 14 No. 1 singles.

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