Speaking to Betsafe, Redknapp recalled the 1994 summer's day at Oxford City - the much lesser known of the two clubs in the university town - when lifelong Hammers fan Steve Davies etched his name into footballing folklore.
It was an unexpected injury and Davies' loudly voiced issues with 'donkey' striker Lee Chapman, a champion with Leeds in 1991/92 before the advent of the Premier League era, that prompted this incredible sequence of events and later inspired a similar storyline with a disgruntled Harchester United fan in the final series of Sky One's cult drama 'Dream Team.'
"We had a pre-season friendly at Oxford City. We split into two teams that day - Frank Lampard Sr. took one half down to Billericay and I took the rest to Oxford City to open their new stadium," Redknapp explained as he turned back the clock 23 years.
"I sat on the bench and there was a guy stood next to me, he got his head in the box right after the kick-off: 'Harry, we ain't got that Chapman up front again this year, have we? He's useless, get rid of him, he's a donkey, why have you got Chapman? Why haven't you bought a centre-forward?'
"He had West Ham tattoos all over his arms, he had West Ham earrings in, Hammers tattoos on his legs. It went on all through the first half, he wouldn't leave me alone, this fella."
With only a limited squad available to him on the day, Redknapp made all the substitutions he had available to him at half-time, only for an injury to then leave West Ham with only 10 players.
"So I turned to the fella who'd been giving me grief all through the first half and I said, 'Big mouth, can you play as good as you talk?'" the ex-Hammers boss continued.
"He said, 'I can play better than that Chapman'. I said, 'Well, come on, get your gear on and we'll have a look at you, you're playing.'
He said, 'What d'you mean?'
I said, 'You're playing'. He said, 'Who for?', I said, 'West Ham'.
'Come on, you keep telling me how good you are, you're playing.
Five minutes later he came waddling back (from the changing room), he had '10 to 2' feet," Redknapp recalled as he sent Davies on in place of Chapman to play centre forward.
"As he went on, the announcer came down to ask 'who's the sub' because they wanted to announce it over the PA system. I said, 'Haven't you been watching the World Cup? Titchyshev, the Bulgarian striker?'.
"Anyway, he came on, went up front, scored a goal, and, to be honest, he was better than Chapman!"
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