Miley Cyrus is tackling the NFL one butt cheek at a time. The 28-year-old singer today announced her week-long collaboration with the NFL Network as she becomes its pre-Christmas Takeover Artist, with that Instagram account getting super-busy promoting it all. Shortly before the weekend, Miley updated for her 117 million followers, and she'd gone both sporty and skimpy. The "Midnight Sky" singer, still celebrating her "Plastic Hearts" album hitting #1 on rock charts, was, per her words, "Serving PUNT." See the naughty action below.