Fighting in Moscow for the first time since being granted Russian citizenship by Vladimir Putin in September, Jones suffered a ninth career defeat and fifth by knock-out.
The 35-year-old got the better of the opening two rounds before the 46-year-old Jones Jr. rallied to get back into the non-title cruiserweight contest in the third. But in the fourth, Maccarinelli dropped Jones Jr with a big uppercut, and although he beat the count to resume the fight, the Welshman pinned Jones Jr against the ropes and stunned him with another uppercut before a right hook sent him face first to the canvas and referee Ingo Barrabas waved off the fight.
The 46-year-old American was once regarded as the greatest pound-for-pound fighter in the world from the mid-1990s for around a decade. Vladimir Putin had signed a decree to grant citizenship to Jones in Sep.,2015 after the boxer announced his intent to apply during an August meeting with the Russian president in Crimea, the territory annexed by Russia last year.
"Well now I am a Russian citizen, so there is all the difference in the world, now I am fighting for my countrymen, now I am Russian the whole public is rooting for me because I am a Russian," Jones said before the fight.
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