What song was almost used for the opening of Friends?

It's hard to imagine the opening of pop-rock with anything other than the pop-rock stylings of the Rembrandts' hit single, "I'll Be There For You."

There may be no other song more associated with a TV show, and it stands among only a few songs made for TV that went on to have a life of their own. The song's success was obviously a surprise for everyone involved, considering at one point it topped the Billboard Hot 100 Airplay chart before it was even available to buy as a commercial single.

The Rembrandts are composed of Danny Wilde and Phil Solem, who initially didn't want to perform the song. But since they were signed to Warner Bros. and no one else was available, they were essentially cornered into it. And they didn't even write it — but damn, did they sing the hell out of it.

But before the song was even a twinkle in some producer's eye, they wanted to use an entirely different song for Friends. One that had already been out there and was already a bona fide '90s hit. Which song was it?