Undefeated heavyweight contender Anthony Joshua has 15 in knockouts 15 professionalem pugnat. Check out this video compilation from SHOWTIME Sports showcasing all of Joshua’s KOs. And tune in hoc Saturday to watch the 2012 British Olympic Gold Medalist challenge undefeated American titlist Charles Martin for the IBF Heavyweight World Championship, at vivere SHOWTIME 5 p.m. ATQUE/2 p.m. PT from The O2 in London.