What keeps him going? Is he fitted with a spring that someone winds up every morning of a match? Has he installed those batteries that power those pink bunnies in the television ads? Is he on some magic potion?
Walsh's explanation for his durability are concentration on fitness and a love for the game that he called “the most important thing”.
“I haven't lost my appetite for the game and that is what keeps spurring me on,” the perennial West Indies fast bowler said prior to the fourth Test against England at Bourda today.
And, he made it plain, he has no immediate thought of retirement.
“If I was to listen to the critics, I'd probably be finished already,” he said. “But I'm still enjoying it, the legs keep answering the balls, the body feels good and, once the body feels all right and the team needs me, I'll try my best to be around.”
“If the body is not going to carry me, then I wouldn't want to play on to embarrass myself, that's for sure,” he added. “And I wouldn't want to let the team down.
“I'm determined to prove people wrong and I feel that once you look after yourself and you keep your body right, you can go on as long as you want,” he said.
There can be no doubt that Walsh is physically fit.
In the 13 years since he made his Test debut in Perth in November, 1984, he has only ever missed one Test through injury – against India in Barbados last season when he strained a hamstring muscle.
No other genuine fast bowler has ever played 100 Tests. The Indian all-rounder Kapil Dev, who opened the bowling at fast-medium pace, had 131 and England's Ian Botham, who can be similarly categorised, had 102.
The only other West Indians to reach the landmark were batsmen – Viv Richards (121), Desmond Haynes (116), Clive Lloyd (110) and Gordon Greenidge (108).
He now has 362 Test wickets, just 14 short of Malcolm Marshall's West Indies record of 376. But he has said his purpose of keeping on is not to surpass his old teammate, now team coach.
Captain at two separate periods for 22 Tests, Walsh was displaced by Brian Lara prior to the current series, a decision by the West Indies Cricket Board (WICB) that caused heated comment through the Caribbean at the time.
“I wouldn't say I was disappointed so much as disappointed in the way it was done,” he said. “I know I wasn't there forever, I indicated that I would play under Brian but I just felt the situation could be handled a lot better.
“The team has always come first for me.”
And he appreciates how important his 100th Test is for his team.
“Even though I might not be showing that I'm hyped up for my 100th Test, the most important thing to me is if we can win this Test match, then I would celebrate my 100 Test matches because I would feel that something right has gone down and we've done well,” he said.