The Lebanese-German, who survived being shot four times in an ambush back in 2015, dropped the tall Russian on his way to a decision victory in Oberhausen.
Ustinov seemed to be getting better of the first few rounds until Charr took over in the mid-part of the contest, putting the 40 year-old veteran on the canvas in the eighth.
‘Diamond Boy’ kept his composure to see out a 116-111, 115-111, 115-112 triumph with the judges and must now make a mandatory defense against Fres Oquendo.
The winner of that bout will then be ordered to tackle current top division king Anthony Joshua by the end of 2018.
In a hastily-announced press release on Friday, the WBA how Oquendo was overlooked despite being stipulated to box for the WBA title in his next fight.
The World Boxing Association (WBA) Championships Committee granted a special permission to boxers Alexander Ustinov from Russia and Manuel Charr from Germany to fight for the WBA Heavyweight Title this Saturday, November 25.
The permission is granted at the request of the interested parties and based on WBA rules C.46 and C.28, also taking into account that the fighters occupy places 2 and 4 of the raking at more than 200 pounds.
However, the winner of this fight must immediately start negotiations with Puerto Rican Fres Oquendo, who has the right to fight for a world title after winning a dispute in a New York court.
This agreement must be made before December 22, 2017. Otherwise, the contest will be called for a purse bid and the percentages will be 50 percent for each boxer.
If the fight between Ustinov and Charr ends in a tie or is not valid, Oquendo must face the next available contender,” said the WBA.