Luke Campbell and Anthony Joshua both moved a step closer to a guaranteed Olympic medal with wins, albeit it by slender margins.
Bantamweight Campbell overcame a sluggish start to battle his way to an 11-9 triumph over Italy's Jahyn Parrinello.
The Hull boxer allowed his opponent to dictate the early stages, although Campbell's success with straight lefts and rights through Parrinello's guard suggested he was a little unfortunate to only tie the first round 3-3.
Although a timely sharp left brought roars from the crowd, Campbell continued to struggle to find his range in the second.
Indeed, the Italian - who had managed an untidy victory in the first round on Sunday - was asking the home favourite plenty of questions.
Yet Campbell deserved to shade the round to move into an 8-6 lead, and although he continued to ship occasional right hands, the 24-year-old edged home to keep his hopes of claiming a medal alive.
Joshua's super-heavyweight bout with classy Cuban Erislandy Savon was even closer, with the man from north London getting the nod by a solitary point.
The 22-year-old from Finchley led 14-12 after the opening two rounds but was forced to weather a comeback in the last, including being rocked by a three-punch combination that forced him to hold on for safety.
In the end the judges gave it to Joshua by a 17-16 scoreline, meaning the world No.3 moves on to the last eight.
It is unlikely the silver medalist from last year's World Championships will come up against another boxer as slick as Savon, the nephew of three-time Olympic champion Felix who was ranked just one place behind Joshua.
Thye two youngsters certainly entertained the crowd in the final fight of the evening at the ExCel, with Joshua drawing loud roars every time he landed a telling blow, most often with his sharp jab or a straight right.