By Jake Donovan

Day Six of Olympic competition continues, with four more evening bouts completing the Round of 16  matchups in the lightweight division. 

Team USA lost five straight heading into Thursday evening and in desperate need of a life preserver. Jose Ramirez wasn't able to stop the bleeding, but certainly left a lasting impression with his brave showing in the Round of 16. 

The Olympic dream ends for Ramirez, who came up short by a 15-11 score  against Fazliddin Gaibnazarov of Uzbekistan.

Ramirez struggled early on and fell into what proved to be an insurmountable hole. Gaibnazarov knew not just what punch to throw during every exchange, but also where to be well before Ramirez was able to get his own offense in gear.

The strategy worked brilliantly for Gaibnazarov, who was up by four points after one and nearly doubled up on that lead three minutes later. Ramirez was instructed by his corner - missing its head coach, Basheer Abdullah - to work off his jab rather than look for counter opportunities.

"We're down seven, so all we need is eight," Ramirez was told by his cornermen, attempting to light a fire.

The conversation took, as Ramirez went balls to the wall in trying to pull off a dramatic come-from-behind win. Gaibnazarov suddenly found himself on the defensive rather than performing the fine art of defense, absorbing power shots as his own offensive output dramatically dropped.

It was a race against the clock, but midnight eventually struck for Ramirez. The late surge was to be applauded, and his fighting style suggests a brilliant pro career awaits whenever he's ready to ditch the headgear and oversized gloves.

Meanwhile, Gaibnazarov advances to the quarterfinals. Awaiting him will be  Soon-Chul Han of South Korea, who squeaked by Vasgen Safaryanta of Belarus via double countback after fighting to a 13-13 tie. 

The combined scoring of the judges saw a second tie, which came down to who each individual judge had winning the fight. Han was declared the winner on three of the five panels, marking the second time on the day in which a verdict came down to a double-tiebreaker.

The evening portion also saw Great Britain's first defeat of the competition. 

Josh Taylor faced an uphill climb in drawing three-time Olympian Domenico Valentino of Italy for the Round of 16. The bout ultimately played out as suggested on paper, even if the judges' scoring took all nine minutes to catch up to the action as Valentino advanced with a 15-10 win.

Valentino was in control for the most part, though Taylor managed to keep things close on the scorecards. On a day when the AIBA caused a major stir in the officiating pool as well as at the executive level, the threat of incompetence still existed in the air.

Then came the third round, when Valentino was finally shown some love. The Italian outscored Taylor 7-3 in the round to pull away with the well-deserved win. 

Great Britain had won five straight bouts, including a dramatic win from welterweight Anthony Ogogo earlier in the afternoon. His means of victory came into question as round-by-round scoring posted on the Olympics' official website didn't jive with what was announced. 

While that matter is looked into (though the initial appeal was denied), Valentino was spared the trouble of having to lawyer his way to the quarterfinals. The three-time Olympian earned it with his fists and will now face  Evaldas Petrauskas of Lithuania.

Petrauaskas surged to the third round of competition on the strenght of a 16-12 upset of the more polished Faith Keles of Turkey. T he Lithuanian boxer attacked from the opening bell, enjoying success with a style better suited for the pro ranks. 

Keles had a hard time adjusting to his opponent's aggression, falling behind early and forced to play catch-up the rest of the way.  Petrauskas never eased off the gas, powering his way to an improbable win and only enhancing his credentials as a promising future pro.

All winning fighters from Thursday will advance to the divisional quarterfinals, which takes place on Monday, August 6. 

Round of 16 Matchups (Thursday, August 2): 
Vasyl Lomachenko (Ukraine) def.  Wellington Arias (Dominican Republic), 15-3
Felix Verdejo (Puerto Rico) def. Ahmed Mejrl (Tunisia), 16-7
Gani Zhailauov (Kazakhstan) def. Jai Bhagwan (India) , 16-8
Yasniel Toledo (Cuba) def. Liu Qiang (China), 14-10
Domenico Valentino (Italy) def.  Josh Taylor (Great Britain), 15-10
Evaldas Petrauskas (Lithuania) def. Fatih Keleş (Turkey), 16-12
Fazliddin Gaibnazarov (Uzbekistan) def. Jose Ramirez (USA), 15-11
Soon-Chul Han (South Korea) def.  Vasgen Safaryanta (Belarus), 13-13 (double-countback)

Lightweight Semifinals (Monday, August 6)
Vasyl Lomachenko (Ukraine) vs. Felix Verdejo (Puerto Rico)
Gani Zhailauov (Kazakhstan)  vs.  Yasniel Toledo (Cuba)
Domenico Valentino (Italy) vs.  Evaldas Petrauskas (Lithuania)
Fazliddin Gaibnazarov (Uzbekistan) vs.  Soon-Chul Han (South Korea)

Lightweights - Round of 32 Results (Sunday, July 29): 
Wellington Arias (Dominican Republic) def. Eduor Marriaga (Colombia), 17-8
Ahmed Mejrl (Tunisia) def. Shafiq Chitou (Benin), 16-9
Felix Verdejo (Puerto Rico) def. Juan Huertas (Panama), 11-5
Gani Zhailauov (Kazakhstan) def. Saylom Ardee (Thailand), 12-12 (Zhailauov wins on countback)
Jai Bhagwan (India) def. Andrique Allison (Seychelles), 18-8
Liu Qiang (China) def. Luke Jackson (Australia), 20-7
Josh Taylor (Great Britain) def. Robson Conceição (Brazil), 13-9
Evaldas Petrauskas (Lithuania) def. Miklos Varga (Hungary), 20-12 
Fatih Keleş (Turkey) def. Abdelkader Chadi (Algeria), 15-8 
Fazliddin Gaibnazarov (Uzbekistan) def. Yhyacinthe Mewoli (Cameroon), 11-6
Jose Ramirez (USA) def. Rachid Azzedine (France), 21-20
Soon-Chul Han (South Korea) dec. Mohamed Eliwa (Egypt), 11-6

Jake Donovan is the Managing Editor for Boxingscene.com. Follow Jake on Twitter:  @JakeNDaBox