Vitaly Klitschko stopped Manuel Charr in the fourth round to retain his WBC world heavyweight title Saturday night in Moscow. The 41-year-old Klitschko won by a technical knockout when the bout was stopped by the doctor with 56 seconds left in the round because of Charr’s bleeding eyebrow. It was Klitschko’s ninth consecutive successful title defense since beating Samuel Peter in his comeback to the ring in 2008. The Ukrainian improved to 45-2 with his 41st knockout. The 27-year-old Charr, a German born in Beirut, dropped to 21-1. Klitschko dominated from the beginning and left little doubt about the outcome. Charr desperately protested the doctor’s decision to stop the fight.