American Andre Ward qualified for Sunday's light-heavyweight final by scoring a tight 17-15 points win over Uzbekistan's Utkirbek Haydarov. Ward, the only US boxer to reach one of the finals, kept his proud country's chances of a medal alive by adopting a high workrate throughout and it eventually paid off when he nicked the extra points needed in the dying seconds of the bout.
In the other semi final Magomed Aripgadjiev from Belarus scored an equally tight points win when he edged out Egyptian hope Ismail Ahmed by 23-20.
The welterweight semi final saw the elimination of double Olympic champion Oleg Saitov when he was out-pointed by 21 year-old Kazakhstan boxer Bakhtiyar Artayev by 20-18.
Though there was hardly ever a point between them, it was the counter-punching Artayev who goes forward to Sunday's final against Cuban Lorenzo Armenteros, who triumphed against Korean Joo Jung Kim by 38-10 .
Other Semi-final results
Mens Flyweight 51kgs
Yuriorkis GAMBOA TOLEDANO CUB w pts 20-11 Rustamhodza RAHIMOV GER
Jerome THOMAS FRA w pts 23:18 Fuad ASLANOV AZE Blue
KIM Song Guk PRK w pts 29-24 Vitali TAJBERT GER
Alexei TICHTCHENKO RUS w pts 45:25 Hwan JO Seok KOR
Light Welterweight 64kgs
Yudel JOHNSON CEDENO CUB w pts 13:9 Boris GEORGIEV BUL
Manus BOONJUMNONG THA w pts 30:9 Ionut GHEORGHE ROM
Gennadiy GOLOVKIN KAZ w pts 23:18 Andre DIRRELL USA
Gaydarbek GAYDARBEKOV RUS w pts 24:18 Suriya PRASATHINPHIMAI THA
Odlanier SOLIS FONTE CUB w rsf 3 Naser AL SHAMI SYR
Viktar ZUYEV BLR wo Mohamed ELSAYED EGY
Atagun YALCINKAYA TUR w pts 26-20 Sergey KAZAKOV RUS
Yan VARELA CUB w pts 29-17 Shiming ZOU
Guillermo ORTIZ CUB w pts 27-13 Bahodirjon SOOLTONOV UZB
Worapoj PETHKOOM w pts 27-19 Aghasi Mammadov AZE
Amir KHAN GBR w pts 40-26 Serik YELEUOV KAZ
Mario Kindelan CUB w pts 20-10 Murat KHRACHEV RUS
Alex POVETKIN RUS w pts 31 19 Roberto CAMMARELLE
Mohamed ALY w pts 18-16 Michel LOPEZ NUNEZ CUB