Head coach Warren Gatland said the Wales team were "shocked" by the news of Rob Howley's alleged breach of World Rugby's betting and anti-corruption regulations.
Wales assistant coach Howley was sent home from the Rugby World Cup on Tuesday with Stephen Jones flying out to replace him.
"We were shocked by it," Gatland told a press conference in Kitayushu on Wednesday morning.
"At the moment these are allegations. Rob is devastated by the allegations."
The 48-year-old former Wales captain has been part of Gatland's coaching team since 2008.
Gatland added: "It took a bit of time to sink in. It is now how we turn a difficult situation into a positive one.
"I texted Rob to see how he got home and that he was okay."
Gatland, 55 on Tuesday, admitted: "I have had better birthdays. But you have to deal with adversity at times.
"The players have really stepped up. We have got to draw a line in the sand.
"My focus has to be on preparing the team for the first World Cup game against Georgia. It hasn't really altered preparations. It will focus us. It is important we focus on the rugby."
Chief executive Martyn Phillips said the Welsh Rugby Union needed to act quickly in sending Howley home.
"We were contacted on Wednesday last week, and then contacted formally with some further information on Friday," said Phillips.
"We needed to be quick and decisive. We were very conscious that we acted in a way you would expect a governing body to act.
"After open training on Monday, we sat down with Rob. He was very co-operative. The formal process will carry on back in Wales."
Phillips said there would be an investigation into Howley's actions and that the WRU would do everything by the book.
He said: "There will be an investigation. It is a pretty serious allegation. The investigation hasn't started. There are other agencies to manage. My focus is on doing it right.
"We have made a change, and I think we stick with that change now. Stephen is coming and he is in for the duration."
Earlier World Rugby said it "fully supports" the Welsh Rugby Union's "proactive approach" over the Howley allegations.
A statement from the organisation read: "World Rugby has been informed by the Welsh Rugby Union of a potential breach of World Rugby Regulation 6 (specifically betting on rugby) by a member of the union's RWC 2019 coaching team.
"World Rugby fully supports the WRU's proactive approach to this matter and can confirm that the union is keeping us informed of their initial discussions.
"It would be inappropriate to comment further​ on an open and evolving process."
The WRU said on Tuesday that Howley had "returned to Wales to assist with an investigation in relation to a potential breach of World Rugby regulation 6, specifically betting on rugby union".
In a WRU statement, they said: "The decision was taken to act immediately in light of recent information passed to the WRU.
"No further details can be provided at this stage as this would prejudice the investigation. If required, an independent panel will be appointed to hear the case.
"Rob has co-operated fully with our initial discussions, and we would ask that the media appreciate this is a difficult and personal matter for Rob and that his privacy is respected before an outcome is reached."
If found guilty, Howley could face the maximum sanction of a life ban from the sport.
Betting on any rugby game is outlawed for the likes of players, coaches and match officials, among others.
Howley is provisionally suspended from any rugby-related activity, pending an investigation.