WASHINGTON (AFP) - Britain's Amir Khan tipped the scales at 139 pounds, one pound less than US rival Lamont Peterson during Friday's weigh-in on the eve of their light-welterweight world championship bout. England's Khan, 26-1 with 18 knockouts, defends his World Boxing Association and International Boxing Federation crowns and an eight-fight winning streak against Peterson, 29-1-1 with 15 knockouts. "It'll get serious now," Khan said. "I will be focused on my game plan." One day after his 25th birthday, the fighter from Bolton, in northern England, looked fit as he weighed in one pound lighter than his career heaviest from July for his fifth-round knockout victory over American Zab Judah. "If I keep training the way I do, I don't think there's anybody out there who can beat me," Khan said. The fight is likely the last for Khan before he moves up into the welterweight ranks, where huge potential paydays against such rivals as unbeaten US star Floyd Mayweather await. But first, Khan must dispatch Peterson and look good doing it. "I'm not looking beyond this fight," Khan said. "I need to win in good style, make some new fans here and put on some fireworks. Everyone will be on the edge of their seats." Peterson appeared well trained also, coming in a half-pound heavier than his last fight, a 12th-round knockout of Victor Cayo in July, and a pound lighter than his draw with US rival Victor Ortiz last December. Dozens of people crammed into a library across the street from the fight venue, the Washington Convention Center, to watch the ceremony. Many of them were name-chanting, horn-tooting, vocal supporters of Khan, who engaged in a staredown with Peterson after both flexed their muscles for cameras. "I've had great support," Khan said. Peterson, once a homeless youth living on the streets of the US capital, is an underdog who feels his time has arrived. "I feel I've progressed enough to become a star in this sport," Peterson said. "I believe that it's my time as a professional to be on top." Khan says it will not be so easy to deny Peterson in front of his family and friends. "It'll be a tough fight," Khan said. "Everyone has made me the favorite but he's in his hometown. He will be up for it and there're two world titles on the line."