Bagshot - Springbok wing JP Pietersen is convinced playing in Japan "opened my mind" though it may not have prepared him for the biggest Rugby World Cup shock ever.
The 29-year-old, whose steps up his quest for a second World Cup title against Wales in a Twickenham quarter-final on Saturday, joined the Panasonic Wild Knights for the 2013-14 Japanese Top League.
Not all countries approve of players going abroad. And there has long been a view that foreign players only joined Japanese clubs, bankrolled by large industrial corporations, for the money.
But with no clash of seasons, Pietersen was able to turn out for the Durban-based Sharks in the southern hemisphere Super Rugby competition.
Pietersen, who has played under New Zealander Robbie Deans, a former Australia coach, at the Wild Knights was in no doubt about the benefits.
"Playing in Japan opened my mind, in terms of running better angles, understanding the game and being in good positions," said 2007 World Cup-winner Pietersen, who has scored 22 tries in his 63 Tests, on Wednesday.
"Japan is a fast game reliant on skills rather than physicality," added Pietersen at the South African team base in Bagshot near London.
"Being coached by New Zealanders and Australians gives you a mix of everything and that helps you come out of a bubble and challenge yourself."
South Africa scrapped a ban on overseas players appearing for the Springboks in 2008 and Australia softened their hard-line stance ahead of the World Cup.
England, however, upheld their policy of picking only home-based players, amid calls for flank Steffon Armitage, who plays for French giants Toulon to be selected.
With England becoming the first World Cup host nation to fail to qualify for the knockout stages, there have been calls for a re-think.
Pietersen is one of many Springboks in the World Cup squad with Japanese connections, including the Suntory pair of Schalk Burger and Fourie du Preez.
Yet despite plenty of 'inside knowledge', South Africa were beaten 34-32 by Japan in their opening match - the biggest upset in World Cup history.
South Africa bounced back to win their next three games to top Pool B.
"It was definitely emotional after the Japan game," said Pietersen. "We opened up and had a hard session with ourselves and what we did wrong. We let ourselves down and our country down.
"That's part of rugby - it's all about testing the character. Our character has been tested since game two."
South Africa coach Heyneke Meyer also told how the defeat reinforced the team.
"Losing to Japan was a very tough day, but we had to learn from it. There have not been leaders in times of peace, it's when there is war that leadership and character come through," Meyer said.
Pietersen added: "I wasn't surprised the way Japan played. That's how they play rugby. Everyone can see now that they play some good rugby in Japan.
"We had analysed them and we were all prepared, but what let us down was our penalties."
Pietersen said discipline would be vital against Wales, who would punish any lapses through the boot of Dan Biggar.
"Wales put pressure on the opposition and they have a good goal-kicker," said Pietersen.
"We have talked about being more patient in defence and not giving away penalties this week."
Saturday's match could be a landmark occasion for South Africa wing Bryan Habana.
The Springbok star needs just one more try to surpass Jonah Lomu's record of 15 World Cup tries and Australia great David Campese's Test career total of 64 tries - the most by a player from a Tier One or major nation.
"He gets better as he gets older," said Pietersen of the 32-year-old Habana, a veteran of 114 Tests. "When we need something big, Bryan Habana always steps up."
"He's one of the great (number) 11s that has played the game," added Pietersen ahead of his 42nd international start alongside Habana.