Pete Townshend was worried about his pal Eric Clapton. The latter had more or less holed himself up in his Surrey home in the English countryside following the break-up of Derek & The Dominos and the deaths of Duane Allman and Jimi Hendrix. He was indulging his heroin habit and wallowing in his unrequited love for Pattie Boyd, the wife of his dear friend George Harrison, and for whom he’d written the impassioned love song “Layla.”

The only time Clapton had recently played in public was at Harrison’s Concert for Bangladesh in August 1971; he’d passed out on stage and had to be revived.

But Townshend figured that the best tonic for Clapton would be to get him out and playing some music with his mates. He arranged to book the Rainbow Theatre in Finsbury Park in North London on this day. (It was actually the Rainbow Concerts, plural, as there was an early and late show.)

The Who leader pulled together a core band of classic rock stars: Ron Wood on guitars, Steve Winwood on keyboards, Blind Faith bassist Ric Grech and Traffic drummer Jim Capaldi, Jimmy Karstein on drums and Rebop on percussion.

The music on the shows wasn’t all that exciting. When six songs including “Badge” and “Little Wing” came out as Eric Clapton’s Rainbow Concert on RSO Records the following September, Rolling Stone reviewer Bud Scoppa described the package as “monolithic melancholy” and “not fun.”

The album was reissued in 1995 on Polydor with 14 songs including eight previously unreleased tracks including “Crossroads,” “Blues Power,” “Bell Bottom Blues” and “Layla.”

Related: Our Album Rewind of Clapton’s lifesaving Rainbow Concert

Nonetheless, Townshend’s tactic did the trick. By the next year Clapton had kicked his heroin habit. He put together a touring band that went into Criteria Studios in Miami and recorded the album 461 Ocean Boulevard that focused on more compact songs and fewer guitar solos; the cover version of “I Shot the Sheriff” was Clapton’s first #1 hit and was important in bringing reggae and the music of Bob Marley to a wider audience.

Related: 10 great Clapton collaborations

Tickets for Clapton’s concerts are available here and here.