Vitali Klitschko says Kevin Johnson could beat him in their WBC heavyweight title bout in December - but won't. The Ukrainian will make his third title defense this year against the unbeaten Johnson on Dec. 12 in the Swiss capital of Bern. “You will be world champion – in the future. But not December 12th,” Klitschko told American at a news conference at PostFinance Arena. “I saw your eyes and I know you trust yourself. I trust myself. Let us see who is better.” Asked if the 30-year-old Johnson (22-0 with 1 draw, 9 knockouts) could defeat him, Klitschko said: “Yes, he can. It will not be easy for me. I am more than sure that it will be a real battle.” Klitschko (38-2 with 37 KOs) stopped Cris Arreola in the 10th round in Los Angeles last month for the American's first loss. Johnson, ranked No. 6 by the WBA and WBC, earned his title shot by stopping Devin Vargas in May in Atlantic City. He said Friday he made a great “promise” by telling his 10-year-old daughter Fatimah he will beat the 38-year-old Klitschko. “I told my daughter this: I will become the heavyweight champion of the world this year,” said Johnson, who raises her as a single father in Atlanta. “I do everything in my life for my daughter. We walk hand in hand, she's like an angel.” While Johnson has won the majority of his fights on points decisions, he has stopped his last three opponents inside the distance. The New Jersey native is 1.91 meters (6-foot-3) tall compared to the 2.02-meter (6 feet, 7½ inches) Klitschko. Klitschko, a three-time champion, is undefeated since losing by TKO to Lennox Lewis in 2003 after a cut opened over his left eye when leading on all three judges' cards after six rounds. He reclaimed the WBC title a year ago when stopping Samuel Peter of Nigeria in the ninth round. Klitschko's younger brother, Wladimir, owns the IBF and WBO titles. Nikolay Valuev of Russia is the WBA champion. Valuev is scheduled to defend his belt against David Haye of Britain on Nov. 7 in Nuremberg, Germany.