Written (by Terry Cashman) and first recorded (as a demo) by Cashman, Pistilli & West (1967).
Hit version by Spanky and Our Gang (US #9/CAN #7 1967).
From the wiki: “‘Sunday Will Never Be the Same’ was written by Terry Cashman and Gene Pistilli, who, with Tommy West, recorded it for their debut album, Bound to Happen, in 1967. Hedging his bets, Cashman also sent a copy of the song to Lou Adler at Dunhill Records, with the hope that The Mamas & The Papas would record the song.
“Cashman recalls: ‘Adler saying ‘Hey, this is a great song.’ But John Philips was doing mostly his own songs [for the group] right now. So, okay, fine. The Left Banke sounded to me also like a group that could do this song, but they also passed on it. And then with nobody else in mind I went to a producer named Jerry Ross, who was [at that time] a very hot producer (‘Apples, Peaches, Pumpkin Pie‘, ‘98.6’).
“‘After listening to about 16 bars Ross took the needle off the vinyl, and he said, ‘Has anybody else heard this song?’ And I said, ‘Well, Lou Adler turned it down for Mamas and Papas, and Left Banke turned it down.’ And [Ross] said, ‘Well, don’t play it for anybody else. I have this great group.’ And he played me a demo of a record that Spanky and Our Gang had done, and they had all these vocal harmonies. A couple of months later he cut the song [with the group], and it was a smash hit. It was something that really put me on the map in terms of the music industry.’
“As on most of Spanky’s hit singles, producer Ross used a group of session musicians to provide the instrumental backing track while the rest of the group members provided lead and background vocals. Session personnel on this record included Vinnie Bell, Al Gorgoni, Hugh McCracken, Charles Macey on guitar, Paul Griffin on piano, Artie Butler on harpsichord, Joe Macho on bass, and Bobby Gregg and Al Rogers on drums.”
Spanky & Our Gang, “Sunday Will Never Be the Same” (1968):