"Rub It In" is a song written and originally recorded by Layng Martine Jr., and credited as Layng Martine. His version, released on the Barnaby Records label, was produced by Ray Stevens and was a chart single in 1971.

Billy "Crash" Craddock covered the song in 1974, on the album Rub It In, taking it to Number One on the country music charts and Top 20 on the pop charts. He told Tom Roland in The Billboard Book of Number One Country Hits that many stations refused to play it at first because they thought it was risque. "I said, 'We're talking about suntan lotion, and if you still think it's risque, then don't play it,'" Craddock said. "Evidently, they all went back and listened to it, and it was the biggest record we ever had." Craddock also made live recordings of the song on 1977's Live! and 2009's Live -N- Kickin'.

Craddock eventually recorded a sequel to the song, “You Rubbed It In All Wrong,” which borrows heavily from the original song's melody but instead replaces the lotion with sand, as the man's lover is discovered to be cheating on him. The sequel was also a top-5 hit on both the country charts.

A third version, in 1999 by country singer Matt King also charted on the country charts, from his album Hard Country. The song's melody was adapted by Glade to advertise their plug-in air fresheners ("plug it in, plug it in").

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