British and Irish Lions flanker Sean O’Brien believes the Lions must lift their physicality ahead of the second Test.
Lions coach Warren Gatland admitted that the All Blacks won the physical confrontation as the Lions went down 30-15 in the first Test at Eden Park.
And ahead of the second Test in Wellington this coming Saturday, O'Brien believes the Lions need to show more belief and not be overawed by the All Blacks.
"It's attitude – we sat off and gave them too much respect," O'Brien told BBC.
"They won [the physical] side of the game, there's no point in saying anything different, so that was obviously a big area for us where we let ourselves down.
"We drew a line in the sand during the week and spoke about the way we'd do things this week. It's about actions now."
Meanwhile, Lions tour captain Warburton says the players have been feeling that they let themselves down this week.
"You play rugby because you enjoy the physical side of the sport – that is definitely the case for me," the Welshman said.
"When you come off second best there, it does hurt you as a player.
"Sometimes you lose games from a bounce of a ball or a controversial decision but when you have been beaten pretty well from a physical side of things – and we were – that is disappointing from a playing perspective."
Warburton has called for a much-improved defensive effort from the Lions if they are to salvage the three-Test series.
"Our first three-phase mentality has to be better, it has to be aggressive," Warburton added.
"You can pick eight sevens [openside flankers] if you want, but if you don't win collisions, it's hard to slow ball down.
"It is a collision sport. Ninety-nine times out of 100, if you win most of the collisions, you'll win the game."