FRANKFURT — Vladimir Klitschko will defend his four heavyweight titles against little-known Francesco Pianeta in May. Klitschko's management says the fight will take place May 4 in Mannhein, Germany. Klitschko holds the IBF, IBO, WBA and WBO heavyweight belts. Pianeta was born in Italy but has lived in Germany since he was six. The 28-year-old challenger has an undefeated record of 28 wins with 15 KOs and one draw, fighting low-ranked boxers. He was briefly Klitschko's sparring partner last year. Klitschko has a 59-3 record, with 51 KOs. “I have a lot of respect for Pianeta because he is young and has a big fighting spirit,” Klitschko said. — Agencies