Eagles were an ascendant country-rock band by 1974, with a handful of hits to their name. With their third album, On the Border, they began courting the rock listeners they so desperately wanted to win over – beginning with the LP's lead single "Already Gone."

The souped-up rock anthem was cowritten by Jack Tempchin, who previously gifted the band their appropriately titled hit single "Peaceful Easy Feeling." "Already Gone" was different: Eagles built it around a rousing guitar riff from their newest member, Don Felder, and his and Glenn Frey's dueling solos.

Eagles had previously invited Felder to play slide guitar on another On the Border track called "Good Day in Hell" in pursuit of a harder rock sound. He arrived at the behest of current guitarist Bernie Leadon, who was a more country-oriented player. Felder and Leadon were childhood friends, and he had jammed with the band in 1972 when Eagles came to Boston as the opening act for Yes.

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Eagles were so impressed by Felder's fretwork on "Good Day in Hell" that they invited him to join the band the next day.

"They wanted to shift from country music to something that could be played on AM radio," Felder told Classic Rock Revisited in 2012. "In the '70s, AM radio had to be a rock track or a dance track or a drippy ballad. They had hits like 'Peaceful Easy Feeling' and 'Take It Easy,' but they really wanted more rock 'n' roll."

Felder's only other On the Border contribution was "Already Gone." He is credited as a "late arrival" in the album's liner notes.

Listen to Eagles' 'Already Gone'

Why Eagles Ditched Producer Glyn Johns

"Already Gone" also marked one of the first On the Border songs recorded after relocating from London to their native Los Angeles and ditching producer Glyn Johns for Bill Szymczyk. The change in atmosphere was immediately evident.

"I had a very strained relationship with Glyn Johns," Glenn Frey wrote in the liner notes to 2003's The Very Best Of compilation. "He was so intimidating, I was always afraid to be forthright and tell him what I thought. ... I was much more comfortable in the studio with Bill, and he was more than willing to let everyone stretch a bit. 'Already Gone' — that's me being happier; that's me being free."

Released on April 19, 1974, "Already Gone" peaked at No. 32 on the Billboard Hot 100 — no small feat, but one that paled in comparison to On the Border's third single, the chart-topping ballad "Best of My Love." More importantly, "Already Gone" set the stage for Eagles' new, harder-rocking direction, which they would further pursue to astonishing success on One of These Nights and Hotel California, the latter of which also featured guitarist Joe Walsh.

"When Joe and I joined, we brought another element to the band that really helped propel them into rock 'n' roll, which took them to a level that the previous Eagles were unable to attain," Felder told Classic Rock Revisited. "We all created something far bigger than any of us would have ever been able to accomplish by ourselves."

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Gallery Credit: Nick DeRiso

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