Boxing is not my game. A punch smack on the nose in my one and only sparring bout brought an immediate end to a never very promising career in the ring. Not so my friend Jimmy. Jimmy was one of the smallest guys in our class. He appeared frail and inoffensive. But the boy could box. Once he stepped into the ring, he was transformed: There was still that diffidence but it disguised a fierce determination, focus and punching power that surprised - and then overwhelmed - many opponents who made the mistake of rating him too lightly. They talk about boxers who punch above their weight: Jimmy was a feather who hit like a sledgehammer.It must have helped that Jimmy's old man knew a thing or two about the fight game. He was respected in our town for two reasons: He taught the local boys how to handle themselves with their fists and he could fix cars. No one in town knew more about counter-punching and carburettors than Jimmy's dad.Outside the ring Jimmy was a fighter too. After being knocked down in his final year at school - felled by a blow in mathematics - he picked himself up, defeated everything that algebra, geometry and trig could throw at him, and became an apprentice fitter before ending up as one of Anglo- American's top designers.In the mining world, Jimmy is one of the few men who can sink a shaft, design the headgear and then climb to the top of the frame to make sure all the nuts and bolts fit perfectly. It's one of the most difficult, and dangerous, jobs in his profession.So when Jimmy says Manny Pacquiao has a chance of beating Floyd Mayweather on Sunday, you need to take him seriously. It's a guarded prediction, based partly on sentiment. Pacquiao, like Jimmy in many of his fights, will go into the MGM Grand arena lighter, shorter and with less reach.Jimmy points out that when it really mattered against top opponents Pacman prevailed. He beat Shane Mosley and Miguel Cotto in the same year. Perhaps those wins took something out of Pacquiao, who lost twice the following year, but is unbeaten in the last three years.Mayweather, by contrast, is indestructible. He has not lost once in 47 professional fights, and seldom looked in danger of doing so. To find the last time someone beat him convincingly you need to go back 19 years, to the US Olympic trials of 1996, when a teenage rival named Augie Sanchez beat him 12-11. In those days it was a best-of-three selection contest and Mayweather came back to win the next two fights, 22-8 and 20-10. A convincing riposte.Mayweather lost again that year, to Bulgarian Serafin Todorov in the featherweight semifinal bout, but the contest was clouded in controversy amid claims of corruption among the judges. Today Mayweather will acknowledge only the defeat against Sanchez as the last time he was beaten "fair and square".On Sunday Jimmy's heart will be with Pacman, but his head will be on Moneyman. And he'll see it all live in Vegas. He had long promised himself a ticket to a big fight, and this one is it. He'll be at ringside, but Pacquiao could do worse than invite him into the corner; after all, Jimmy knows a bit about the fight game...