Undefeated heavyweight contender Anthony Joshua has 15 knockouts na ya 15 ọkachamara ịlụ ọgụ. Check out this video compilation from SHOWTIME Sports showcasing all of Joshua’s KOs. And tune in a Saturday to watch the 2012 British Olympic Gold Medalist challenge undefeated American titlist Charles Martin for the IBF Heavyweight World Championship, na-na showtime na 5 p.m. NA/2 p.m. PT from The O2 in London.