British & Irish Lions captain, Sam Warburton, believes Warren Gatland's team must become the best team in the world in order to beat the All Blacks in their series in New Zealand.
The All Blacks hold a 29-6 lead over the Lions in the 38 games played [three draws] so far between the sides, with the Lions' only series win coming in 1971.
"To beat New Zealand, who are the best team in the world, that means that we have to become in six, seven, eight weeks time, whenever the first Test is, we have to become potentially the best team in the world to be able to beat them," Warburton told BBC Radio Wales.
"That is the challenge. Doing that within the next short time period. It's going to be different [than four years ago]. I think it is going got be very difficult.
"Four years ago there were chances for guys to have a little bit of a social together, might be able to go out, have a couple of beers and do things like that, which is quite a good way to get to know players."
But Warburton, who has played six times and lost six times against New Zealand for Wales, insists that could prove difficult on this tour with a schedule that sees the Lions play 10 games in 36 days.
"The games are coming so thick and fast there is not going to be any time for stuff like that really. I think going through difficult training and games is what bonds players," he continued.
"When you go through all the emotion and the pressure of a week-building towards a game and you go through the emotions of a game and afterwards when you celebrate in the changing rooms.
"Nothing builds that from a team perspective, going through wins or losses in bringing teams closer together. The fact there is quite a lot of warm-up games, every game we knit closer and closer together as a squad."