The then 23-year-old flanker was sent off early for a tip tackle on French winger Vincent Clerc, reducing Wales to 14-men for the remainder of the match. France would go on to win the match 9-8 in a tight affair and face the All Blacks in the final.
Although most of the reaction was supportive of Warburton, a few supporters pinned blame on the young flanker and one went as far as sending a death threat.
“I got a death threat sent to the house,” Warburton explained.
“Well, they sent it to the Cardiff Blues and they obviously didn’t know what was in it.
“People write to the WRU [Welsh Rugby Union] or the Blues because they know the address and then the Blues might send you an elastic band’s worth of about 10 letters.
“I opened up one and there were skulls and coffins on it, there were drawings saying what would happen if I ever went out of the house.
The threat didn’t phase the Welsh captain, with the overzealous nature of the letter failing to scare.
“It was so over the top that I thought it was a bit of a joke and it didn’t bother me. But that was the only bad thing I got.”
Warburton, who retired in June at age 29 over concerns of his long-term health, said he received overwhelmingly positive support following the World Cup.
“I was in a supermarket late at night and middle-aged women were coming up and hugging me.
“Then there were cars pulling up outside my house – it was obviously kids realising where I lived – and they were blasting out the ‘Sam our Captain’ song.
“I was getting a massive amount of support and it did soften the blow.”
Warburton went on to captain Wales 49 times in 74 games for his country, as well as captaining the British & Irish Lions on two tours, beating Australia 2-1 in 2013 and drawing with New Zealand 1-1 last year. The final drawn test at Eden Park ended up being his last ever test match.
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