Mike Ruddock has lauded Colin Charvis for the way he has responded to his Wales coaching regime. The flanker lost the Wales captaincy to Gareth Thomas, but has enjoyed a superb autumn and will lead the side in Thomas' absence against Japan.
"Colin has been magnificent in his new role," Ruddock told BBC Sport Wales.
"His game has improved, I think because responsibility has lifted, but for Japan he is a natural, experienced leader who the players respect hugely."
Ruddock says that Charvis, 31, responded maturely to the decision to strip him of the captaincy after the summer tour.
"I tried to put my mark on the team, and I hope that has worked," said Ruddock.
"Gareth has been inspirational as a leader, the players follow his example and it's had a big effect on the team.
"As disappointed as he was to lose the captaincy, Colin is an intelligent guy and he could see where I was coming from.
"I wanted to free him up to concentrate on being one of the most effective open-side flankers in the game. "He gives natural leadership in and around the ruck, line-out and scrum areas and really influences the team."
Ruddock's praise was supported by former Wales number eight Stuart Davies, who played alongside Charvis for his country and for Swansea.
"There's no doubt he [Charvis] has been Wales' man of the autumn series," Davies told BBC Wales.
"He's taken his game to another level, and that's quite an achievement when you consider his advancing years and the position he's playing in.
"He responded in a remarkable fashion to his demotion, being totally supportive of Gareth Thomas.
"It was a testament to the man, and it is quite right he should be restored to the captaincy against Japan."
Charvis will be winning his 75th cap on Friday night.