Before Sergio Martinez became a most unlikely boxing world champion, he spent his formative years as the most likely robbery victim in the small Argentine barrio he called home. Thieves did not rob Martinez once, or twice. They robbed him at least 10 times.

Today, Martinez is a middleweight with 27 knockouts, as feared as any fighter, his left hand his only necessary bodyguard. Back then, neighborhood thugs took, according to his recollection, his watch (twice), sandals, shoes, wallet, cash, documents, bicycle, T-shirt and, once, a single peso.

“One day his computer school was closed,” Martinez’s father, Hugo, said recently in a telephone interview from Calzadilla, Spain. “Someone hit him with a gun in the eye. It was purple, bruised. We joked about his bad luck with robberies. It seemed like, if Sergio left the house, he got robbed.”

Hugo Martinez laughed. “I can tell you more stories about robberies,” he added.

One robbery changed Martinez’s life, led him to Italy, then Spain, then California, into boxing, where he is generally considered the world’s best fighter not named Mayweather or Pacquiao. Martinez is scheduled to fight Matthew Macklin on Saturday at the Theater at Madison Square Garden.