Springbok coach Heyneke Meyer has issued an apology to his country after the extraordinary loss to Japan in Brighton.
He has described the performance as "unacceptable".
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Speaking to the media after the Pool B match at Brighton, Meyer said: "I have to apologise to the nation. It was just not good enough. It was unacceptable and I take full responsibility."
Japan captain Michael Leitch said: "I always knew it was going to be a big battle...David v Goliath. We've been training for this day for the last four years. We've worked extremely hard, all the coaching staff and the players. It was just a full-on team effort. The Springboks came out and just tested us but we knew if we just kept it on we'd come away with the win.
"I'm not surprised. We came out here to do a job. I know the whole world is surprised but in our camp, we always knew we could do it."