Home advantage is one of competitive sport's key tropes. It is regarded as such an important influence on the outcome of football matches -- in which it is rare to win with a lead of more than a goal or two and draws are common -- that in some home-and-away tournaments, away goals count double.
Sometimes home advantage takes on mythic proportions. It is, remarkably, 20 years since the All Blacks lost at Eden Park. (I was there and it was not a good day.)
There are any number of reasons that home advantage might matter: familiarity, knowledge of local conditions, players are happier near to their loved ones and, of course, the motivating infleunce of a partisan home crowd.
After the All Blacks' loss to the Springboks at Ellis Park over the weekend I think it's become clear that in modern international rugby, there is a new element to home advantage: control of the television pictures.
Let's be clear about this: the Springboks richly deserved their win. Their backs played some fluent, creative rugby, they have a new star in Handre Pollard, and their forwards unsettled the All Blacks in a way few sides have done in recent years. If nothing else, they showed how well you have to play to beat the current All Blacks.
But after an impressive All Black comeback, the match turned on Patrick Lambie's long-range penalty in goal in the dying minutes of the game. Both Wayne Barnes (who had a pretty good match) and his assistants missed the incident that led to the penalty and play had moved on well down the field, where the All Blacks were about to feed a scrum.
But the South African TV team saw it and replayed the footage. We viewers saw it and so did the crowd at the ground, who responded noisily.
The South African captain Jean de Villiers eventually asked Barnes if he would check the replay and Barnes (although he had told Kieran Reid in the first half that he could not check a replay at the request of a player) then asked his assistant ""Is there anything to have a look at?"
There was. Back in the Bok half, Dane Coles had tackled Schalk Burger around the ankles, meaning he fell into the tackle of Liam Messam and copped a fair old whack on the head on the way down. It was, everyone agrees, an accident, the kind of thing that is sometimes penalised, sometimes not.
But after the impact had been played through several times in close-up, with the crowd roaring, there was little scope for Barnes to not award the penalty --- on the basis that Messam had made contact with Burger's bonce.
Would it have played out the same way in Auckland, or any other ground in New Zealand? No. We'd have had the home TV advantage. The replays would have been celebrating Reid's good work in securing the scrum feed the All Blacks would otherwise have been having. We've benefited in the same way before, I'm sure.
So yes, great win to the Boks. But the much greater role of video replays in the modern game might cause an interesting situation in next year's Rugby World Cup in Britain Let's say it's a dour semifinal that England have managed to keep close but the All Blacks seem to have secured it. And then a possible offence 40 metres away starts looping in the TV coverage and on the big screens at the ground. Can it be ignored? And is there such a thing as a neutral host broadcaster?