Coming into the ring with an impressive 15-0 record with 11 stoppages, Liebenberg survived an early cut to inflict a third straight loss on Grachev and take a unanimous verdict after twelve rounds.
The South African carded scores of 120-108, 117-111 and 116-112 to move on to a big night in Monte Carlo on October 25, fighting on the same bill as Martin Murray’s middleweight clash with Domenico Spada.
In the co-feature, the now former IBO super-bantamweight champion Thabo Sonjica came through Roli Gasca with ease, although left the arena without his title belt having lost it on the scales on Friday.
The southpaw was put down in the seventh by a sweet shot from Gasca, but retaliated himself to score a knockdown of his own in the eleventh, before going on to record a 117-109, 116-109 (twice) triumph in front of his home fans.
Also on the bill, undefeated cruiserweight prospect Kevin Lerena pushed his winning streak to ten since turning pro as the 22 year-old out-pointed Marcos Ahumada 79-73, 78-74 and 77-75 after eight rounds were completed.
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