Washington, Apr 8 : Carrie Underwood says she was mortified when she made a sexual reference joke to wanting to see Matthew McConaughey''s "boots" in her acceptance speech at Sunday''s American Country Music Awards.

Before presenting Underwood with Entertainer of the Year, McConaughey told the audience how George Strait''s boots once got him "lucky."

"We''re like, ''Oh yeah. Say, as I a matter of fact, out in the parking lot, in the trunk of our white Corvette, we have the next year''s new edition white ostrich quill George Strait signed series that he''s gonna wear on tour next year.'' And they got pretty excited about that and said, ''Well, can we see? Can we see? Can we see?''" McConaughey told the audience.

"And we obliged ... Point of the story is, we got lucky that night. Thank you, George," he added.

As Carrie accepted her trophy from Matthew, she grabbed a few laughs as she remarked, "I don''t know what to say. I got nothin'' ... I want to see those boots, Matthew."

Now, the stunning singer told Fox News: "I''m so embarrassed, I totally embarrassed myself. I just blanked.

"You want to say something eloquent in a moment like that and I embarrassed myself. I''m sorry Matthew, I''m sorry to my family. I''m totally embarrassed." (ANI)