Timothy B. Schmit joined just in time to watch the Eagles disintegrate. Ironically, things couldn't have started in a better place for the former Poco star.

He already had the makings of his first showcase moment with the group, an unfinished track that would become the February 1980 hit "I Can't Tell You Why."

"I did bring a portion of that song, unfinished, to them back then – because I was new in the band and they wanted to introduce me on a good note, no pun intended," Schmit told Songfacts. "And I had this little piece of a tune that they really liked. It was loosely based on my own experiences."

For a moment in time, often contentious band members rallied around the outsider. Don Henley and Glenn Frey both made key contributions, as the group completed the first song on what would become 1979's The Long Run. Schmit felt like he had good reason to be optimistic.

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"I think probably the friction was part of the creativity. I'm sure it was," he told NPR. "I was the guy just trying to make things okay. I did what I can to keep the peace."

Schmit had established his country-rock credentials with Poco, but by the late '70s, the Eagles had long since left those rootsy sounds behind. They wanted to push Schmit in the same direction, crafting an R&B-infused setting for his embryonic ideas.

"Timothy joined the band and the real challenge, as Don and I saw it, was to get a piece of material for him that wasn't country," Frey told Cameron Crowe. "So ... the three of us got down to work. I said, 'You could sing like Smokey Robinson. Let's not do a Richie Furay, Poco-sounding song. Let's do an R&B song.' He said, 'Sure, love to try!'"

The Detroit-bred Frey, who had deep roots in soul music, took the lead – literally. He was the featured guitarist in the studio rather than Joe Walsh, who instead provided all of the song's keyboards. (The official video and live performances found others playing Frey's solo role.)

"Glenn worked everything out," Schmit told Rock Cellar magazine. "We used to call him 'The Lone Arranger.' He was so good at that, so good at figuring out parts and what should lay there."

Listen to Eagles' 'I Can't Tell You Why'

'There's Your First Hit'

The Eagles' sweet vocal mix completed things. "Timothy came in with the title and other bits and pieces," Henley told Crowe. "Glenn and I just wanted to surround it with everything we could."

As foreign as "I Can't Tell You Why" was to earlier stand-out Poco moments like "Rose of Cimarron" and "Keep on Tryin,'" the song actually recalled a youth spent around a broad variety of music.

"Even though I grew up playing folk music — and surf music, originally — I was listening to Motown and Stax on the radio, as well," Schmit told Best Classic Bands. "That music always resonated with me. I was very pleased that the song they picked to work — and the one I was going to sing — was not country-flavored, or something that went in another direction. I was really happy to go in an R&B direction. Thrilled, actually."

It quickly became clear that something magical was happening.

"I remember when it was being developed in the studio, I knew it was a great song," Schmit told Music Radar. "I was like, 'Yes! This is an amazing debut for me.' When we finally mixed it, we had a little listening party at the studio. As people were hearing it, Don turned to me and said, 'There's your first hit.' That was pretty cool."

Henley was right. Released as the third single from The Long Run, "I Can't Tell You Why" became the album's third-consecutive Top 10 Billboard smash, mirroring the No. 8 finish of its title track.

Listen to Eagles' Live Version of 'I Can't Tell You Why'

Then His New Band Promptly Disintegrated

"It was all such a great ride. I just kept pinching myself," Schmit told Music Radar. "I was pretty happy they wanted to work on the song, but I probably had a few other things I showed them, too. You really don't know what's going to be a hit until it's a hit."

Then, just months after "I Can't Tell You Why" raced up the charts, Schmit's crumbling new band went on a lengthy hiatus. A fast start now long past, he wasn't featured on another Eagles song until 1994's "Love Will Keep Us Alive."

Schmit kept it all in perspective: "You get asked to be part of one of the biggest bands in the world, and the first song you record is a song you helped write and you hear it on the radio, it's good – it's great," Schmit later told Vintage Rock. "I'm really, really fortunate. There's a lot of real talented people out there with much more talent than me who just don't get these kind of chances."

Years later, it remained one of the late Frey's all-time favorite Eagles moments. He wasn't alone.

"It’s got the mood; It’s got the 'ooh baby, baby' vocal. But, again, counterpoint — with Don and I singing against the melody and the understated, brilliant guitar stylings of yours truly," Frey told Crowe, with a laugh. "It's another song that people love in our live show. Since it is a ballad, we are not playing too loud and can hear the audience. Timothy starts, and there are thousands of people singing, 'Look at us, baby ...'"

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