Great Britain's reigning boxing world champion Savannah Marshall suffered a 16-12 defeat in her opening women's middleweight bout to Marina Volnova of Kazakhstan.
Marshall lacked a little timing in the early stages against the former world silver medallist, who lunged in with right hands and had some success in knocking the Hartlepool fighter out of her rhythm.
Marshall began to land right hands in the second, but Volnova also stepped up the pace, bulling side and finding some success with uppercuts, and at the halfway stage of a nervy affair the score was level at 7-7.
Two heavy right hands helped Marshall nudge ahead early in the third but Volnova was proving a tough character, coming back and producing the majority of the cleaner work with both fists to take a two-point lead into the last.
Predictably Marshall came out fighting, but she was missing too much and the cagey, compact Volnova did what she had to do to deal a crushing blow to the Hartlepool fighter who had hopes of gold.