Undefeated heavyweight contender Anthony Joshua has 15 knockouts katika yake 15 mapambano mtaalamu. Check out this video compilation from SHOWTIME Sports showcasing all of Joshua’s KOs. And tune in Jumamosi hii to watch the 2012 British Olympic Gold Medalist challenge undefeated American titlist Charles Martin for the IBF Heavyweight World Championship, kuishi juu ya Showtime katika 5 p.m. NA/2 p.m. PT from The O2 in London.