Israeli heavyweight Roman Greenberg maintained his flawless record late Saturday night by knocking out American Steve Pannell in Hollywood, Florida. Greenberg, who improved his record to 24-0 with 17 knockouts, was unconvincing in the first two rounds but floored Pannell (34-11) in the third round and was awarded the victory with 36 seconds to go after the American hit the ground for a third time. "It took me a little while to warm up and to work him out," Greenberg said after the fight. "We knew we were going to finish him off when he attacked and we worked on that in training." The 24-year-old Greenberg, who held onto his IBO Intercontinental heavyweight belt, has no further fights scheduled for this year and in 2007 will be hoping to make further progress towards a fight for a heavyweight world championship.