He has played Test rugby for almost a decade and has experienced virtually everything the game could throw at him, but Jason White is still haunted by a fear of failure every time he pulls on a Scotland jersey.
And the 30-year-old flanker will use that to ensure he does not let his country down when he makes a rare start at lock in Sunday's RBS 6 Nations opener against Wales.
Sale star White, who will win his 70th cap at Murrayfield, was drafted into the second row yesterday after Nathan Hines failed to recover from a knee injury.
It will be the first time he has started a Scotland match in the role for more than six years and only the fifth occasion since his debut in 2000.
The fact White was preferred to recognised locks Alastair Kellock and Craig Hamilton tells all three players where they stand in the estimation of the selectors.
It is still an added burden for White, who revealed he has seen enough in his career to be unfazed by almost anything - but is still apprehensive when playing for his country.
"I suppose I've been lucky to encounter most things," he said.
"But I still have the fear of not playing well enough for Scotland and not being as good as I can be."
At the same time, White is confident of rising to the challenge on Sunday.
"Am I worried about playing Wales at the weekend? No," he said.
"I've got a strong belief in my ability and a strong belief in the other seven forwards in the forward pack and the rest of the players in the team."
Although White's Test experience at lock is limited, he played most of his junior rugby in the position and has filled in there for Sale this season, including during last weekend's Guinness Premiership win at Worcester.
Yet he admits he is not in the ideal shape physically to play the role.
"In terms of conditioning, I'd say primarily you want to be heavier," he said.
"That's the down side obviously. I'm not quite as heavy as Nathan is in terms of scrummaging.
"Hopefully, I'm naturally strong. So I'm going to get in there and ruck as hard as I can."