"What better way to launch Season 13 than with a new song that @Pink wrote just for me? Today’s the day!" DeGeneres tweeted, along with a video of Pink recording the song -- called, yes, "Today's the Day."
The singer's 4-year-old daughter Willow also makes a guest appearance in the video.
"Somebody please stop the clock/Oh, Never let this day stop," Pink sings. "Today's the day I been waiting for/Tomorrow won't come after all/Yesterday's so far away/I guess today's the only day."
The new season of "The Ellen DeGeneres Show" starts Sept. 8.