Give a dog a bone, and it won't let go. Give a golfer a scent of a major and, well, then we get to see what he's made of inside. Is he tough? Or is there a soft underbelly? Padraig Harrington, we know, is not soft. When it comes to the hard call, he takes the aggressive approach. Time, after time, after time.
At Augusta National, there is no place to hide because all of the questions asked are difficult ones. On each occasion that Harrington has played in the Masters, he has learned. "You do have to serve an apprenticeship in the majors," he conceded, "you have to contend and learn from it, but I am getting further down the line. I've committed myself to preparing for the Masters this year and I've put in the right preparation.
"But I'm not going to beat myself up if it is not ready. I know that I've done everything that I can do."
The times when he was an unknown in the United States have long gone. Among those to sit up and take notice of Harrington's emergence is Fred Couples, who remarked: "Any time you talk about a possible tournament winner, you have to throw Padraig Harrington's name into the hat.
"He can win. He works hard and knows how to work his way around the course. He has got a lot of fight in him. I do like the way he plays."
Harrington's previous visits here have seen him survive the mid-way cut and more on each occasion. On his debut in 2000, he finished tied-19th; in 2001, he finished tied-27th; and then, last year, he finished in tied-fifth position.
"It's always great to be here, and it doesn't really lose anything over time. It is a very special place, a great place to come and play golf," he said.
So, yes, he is comfortable in the Augusta National environment, on a course that demands long hitting off the tee - especially in these wet conditions - and a thinker's mind, where you plot your way around.
After his fifth-place finish a year ago, and his elevation in the world rankings to eighth, which makes him the leading European, does he come into the event merely seeking to improve on last year's finish? And it is then that you get the real insight into Harrington's thought process.
"No, it wouldn't give me any pleasure to come in here and finish fourth. Okay, so I'd probably be happy to do it at the end of the week . . . but I wouldn't be setting out to do it. Even if I finished second, I'd go away very unhappy. I'm not here just to make up the numbers."
Harrington has climbed the graph of expectation and for him winning is what the game is all about. For a time, finishing the job proved to be difficult and he has 17 runners-up positions in his career on which to reflect.
However, he has won six times on the European Tour as well as triumphing in the World Cup (with Paul McGinley, in 1997) and, also, going head-to-head and beating Tiger Woods in the Target World Challenge, an unofficial tournament in America last December.
That win in the World Challenge was the icing on the cake for an exceptional finish to 2002 which had seen him play a role in Europe's Ryder Cup win and then follow up with wins in the Dunhill Championship and the Asian Open.
So, is he ready to win a major?
"I'll take my chance when, if, it comes round, that's all you can do. I've got to say that if you get a chance, you try to take it and give 100 per cent," replied Harrington, adding only half-jokingly: "I don't know what size jacket I am. But any size will fit me this week."