Richie McCaw has admitted that he made a "dumb mistake" during New Zealand's opening win over Argentina at the 2015 Rugby World Cup.
The All Blacks captain spent 10 minutes in the sin bin at the end of the first half after tripping Juan Imhoff during the 26-16 win at Wembley.
The 34-year-old told reporters: "It was a dumb mistake I made. But you can't worry about those sort of things, it is what it is.
"It's happened before, there's no good getting worried or all wound up about it. That's not going to help you. I guess it's a way of trying to put you off but you've just got to block that sort of stuff out.
"It was one of those things that as soon as it happens you wish it hadn't. I knew straightaway, it was a reflex thing and it wasn't the right thing to do. We suffered because of it and I put the team under pressure because of it."
McCaw has seen yellow three times in his 143 appearances for New Zealand.
