According to Ian Chappell, originated in Adelaide during the 1963/4 or 1964/5 Sheffield Shield season. A cricketer who swore in the presence of a woman was taken to be as subtle as a sledgehammer (meaning unsubtle) and was called “Percy” or “Sledge”, from singer Percy Sledge (whose song When a Man Loves a Woman was a hit at the time). Directing insults or obsenities at the opposition team then became known as sledging. (Reference: The Lingo: Listening to Australian English, Graham Seal, University of New South Wales Press, 1999, ISBN 086840-680-5, page 141.)Odd that my namesake didn't release said song until 1966.
Maybe Chappelli had psychic powers?
OK ... some further investigation.
Let's be fair to Mr Seal.
He writes: "About the same time ..."; not "at the time".
Here's a clip from his book:
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All this gets more interesting on consulting the great Ramson (Aust Nat Dict) who manages to find this original from the SMH, 4th November 1982:
The court [which I wonder?] has been told by Ian Chappell that the expression "sledging" first came into vogue among cricketers in 1963–64. It came from the expression "subtle as a sledgehammer" at a time when a man called Percy Sledge had a song on the English hit parade. It meant using words to exploit an opponent's weaknesses and put him off his game. [My emphasis]"When a Man..." was PS's first US (#1) and UK (#4) hit and it wasn't even recorded until 1966.
He was unknown until then.
Indeed, he was no more than "a man called...".
Now, should I go into the business of properly citing one's sources?
Hmm ...
No ... I'll leave that to the bloody pedantic Prof.