Richie was so keen on the Argentina bottle that he knocked over the All Black one in order to get a better drink from it.
Mr Underwood, 22, said Richie might have been channelling the nation's concerns that the All Blacks cannot win without Carter.
But despite Richie's dodgy prediction, Mr Underwood still has faith in the team and is betting against the young bull that the All Blacks will triumph over the Pumas.
"Personally, I think the All Blacks will still win the World Cup - they're still a great team, even without Carter."
Mr Underwood said Richie's other predictions for the World Cup quarter-final matches were slightly more credible, and he thought the bull made some "sensible" picks.
Richie set off at a run at the Ireland bottle and ignored the one emblazoned with the Wales flag.
Move over France, your time in the cup is over - Richie picked arch-rivals England to knock Les Bleus out of the tournament.
"I think they will beat England - France has been pretty crappy so I think that might be right," Mr Underwood said.
On Australia, "that could have been anyone's call really. Who knows who'll win that one?"
Richie so far has a 75 per cent hit rate - correctly predicting three of New Zealand's four pool-match results.
The young bull has beefed up considerably since the Herald first introduced him to the world and has sprouted a small set of horns.
Mr Underwood admitted he had been spoiling Richie after the bull received international attention when he was deemed a good omen from the sporting gods for the All Blacks during their World Cup campaign.
All black, except for a silver fern on his forehead, Richie was the cream of the crop from the day he was born.
But he has become demanding after all the attention and special treatment, and got a tad stroppy as he was making his picks.
Richie reckons...
* Ireland v Wales: Ireland
* England v France: England
* Australia v Springboks: Australia
* All Blacks v Argentina: Argentina.