London - Dan Biggar said he is the "least confident person there is" but, fortunately for Wales, his lack of self-esteem only applies to his life off the rugby field.
The flyhalf has been in hot form for Wales ahead of their Pool A decider against Australia at Twickenham on Saturday.
Wales are already in the quarter-finals, but Biggar will be again expected to steer his side round Twickenham - a role he performed impressively scoring 23 points in their 28-25 win over England two weeks ago.
No-one watching Biggar's performances for Wales would have detected a lack of confidence.
Yet the 25-year-old veteran of 37 Tests said it was only on the field that he felt truly able to relax, for all the pressure that comes with playing in such a pivotal position as fly-half.
"I think probably off the field I am the least confident person there is," Biggar told reporters at Wales' hotel ahead of Saturday's match.
"I don't really enjoy the limelight at all in terms of what comes with it. When I am on the field it is when I am most comfortable and almost when I can relax a bit more in terms of knowing what I'm doing.
"The frustration from some friends and family of mine is sometimes rugby is all they want to talk about.
"But I guess if you are an accountant, you don't want to talk about numbers and figures when you go home each evening," the Ospreys No 10 added.
"It's great that we can go home and relax and put anything other than rugby on and forget about rugby just for those days. It's important to come in fresh to go."
Wales, who have won all three of their 'Pool of Death' matches so far, will face either Scotland or Japan in the knockout phase if they record a first win over the Wallabies since 2008 this weekend.
But defeat against Australia, also unbeaten at this World Cup, would see Wales up against two-time world champions South Africa in the last eight.
Wales have lost their last 10 Tests against Australia but Biggar took heart from the way the team upset the odds to beat England, a match in which the Welsh were three-times behind by 10 points.
"Playing England at Twickenham nobody gave us a prayer, and everyone is talking up the Wallabies this week, and quite rightly so as they are an outstanding team," Biggar said.
"Their backs are looking sharp, and they played some really good rugby against England, so it is going to take a heck of a defensive effort from us.
"But we went to Twickenham and beat England in their own World Cup, so we have got to go in there with plenty of confidence and back ourselves to come out on top, although we are fully aware how difficult it is to beat the Wallabies."
Wales have been beset by injuries, including losing ace goal-kicker Leigh Halfpenny before the World Cup started.
Yet the likes of Biggar, given goal-kicking duties in the full-back's absence, have filled the void admirably.
"We have had so many injuries, we have had so much publicity about that, and it has brought us all together and we are just worried about ourselves and thinking whoever we play - Scotland, Japan or South Africa.
"It's going to be a heck of a Test match, but one which we are going to relish," Biggar said.