Stephen Jones has reflected on a "manic" week that saw him answer Wales' World Cup SOS following Rob Howley's departure from Japan.
The former Wales fly-half has taken on attack coach duties, arriving last week after assistant coach Howley was sent home for an alleged breach of World Rugby's betting regulations.
Howley, 48, is back in Wales to assist with an investigation relating to a potential breach of World Rugby regulation six - specifically betting on rugby union.
Jones had already been named as part of a new post-World Cup Wales coaching team under Wayne Pivac, but he is now an essential part of the campaign for global glory.
Asked if it had all been a whirlwind, Jones said: "Yes. You have pretty much hit the nail on the head there.
"It's been manic, if I am honest, but what a wonderful welcome I have had from the boys and the management.
"I have worked with a number of the players and management before. The senior players were excellent - they took the helm and took the lead - which was great."
Jones, who said he had not had chance to catch up with Howley, was at home in Cardiff when he received the call, and he added: "It was a bit of a shock.
"When I got the call, it was a straightaway decision. I am very fortunate that I have a supportive wife as well! It was an instant decision.
"Obviously, there is a wonderful foundation in place. There are a lot of good things in the library already.
"'Gats' (Wales head coach Warren Gatland) has been excellent and said I can evolve things slowly, but obviously I am conscious there is going to be limited grass time, but where I am fortunate is that there are so many good things in place.
"It's a wonderful environment. You look at each department, how they function. Everybody knows their role, and they do it very well from a management perspective."
Wales have arrived in Tokyo from Toyota City, where they beat Georgia 43-14 in their Pool D opener, with Australia looming in five days' time.
But Cory Hill's hopes of playing any part in the tournament are over after he was released from Wales' World Cup squad.
The Dragons lock was named in the group and travelled to Japan, but he has not been able to recover from a stress fracture of his fibula.
Hill, who last played in February, will be replaced by 65 times-capped Ospreys forward Bradley Davies.
Wales had hoped that Hill would be available to face Australia, but he has run out of time.
Hill's fellow lock Adam Beard, meanwhile, only arrived in Japan three days ago after having his appendix removed.
Skipper Alun Wyn Jones and Jake Ball are set to continue as Wales' second-row partnership against Australia, with flanker Aaron Shingler providing lock cover on the bench.
Looking ahead to the Wallabies clash, Stephen Jones said: "It will be a massive occasion, and it's one as players and coaches that you love - big sporting moments.
"We have some things to evolve quickly and improve, which is great.
"It's about playing smart, recognising how the opposition set themselves up. From an attacking perspective, you have to have the ability to shape the opposition's defence.
"It's about being smart with the ball - you don't want to waste your energy in certain areas of the park. When you get in the right areas, you need to convert your chances and be potent.
"They have lots of talented players, but I look at it from our perspective, and our boys will be looking forward to that challenge of going up against those boys.
"We have got some wonderful players regarding skill-sets, athletic ability, work-rate off the ball. It's exciting from our end."