Delante Johnson became the first U.S. welterweight to advance in Olympic competition following his split decision win over Argentina's Brian Aguerri. Scores were 29-28 on three scorecards for Johnson, and 29-28 on the other two cards.

Full recap can be found HERE.

Stephen Zimba (Zambia) closed out Day One of the welterweight bracket with a clean sweep of Samoa's Marion Faustino Ah Tong. Scores were 30-27 across the board for Zimba, who will next face number-two seed Andrei Zomkovoi (ROC) on Tuesday.

Eskerkhan Madiev was the first boxer from the Republic of Georgia to both appear and win in Tokyo. It came in anticlimactic fashion, as Azerbaijan's Lorenzo Sotomayor was deemed unable to continue following a cut suffered in round three. 

The bout was nip and tuck, with both fighters claiming 3-2 splits in the rounds they won. Sotomayor attempted to pick up the aggression in round three, only to suddenly no longer be able to continue as referee Miguel Anco Bobadilla called for a stoppage due to cuts. Sotomayor justifiably protested the call but nevertheless was sent home. 

Madiev will next face Shadiri Bwogi (Uganda) on Tuesday. 

Vikas Krishan entered Tokyo 2020 sharing history with Vijender Singh as the only fighters from India to qualify for three separate Olympic games. 

The third time was not the charm for the 29-year-old, who was eliminated from competition by Sewonrets Okazawa who gave hosting nation Japan its second win of the day. Okazawa won a three-round unanimous decision in an awkward fight that saw several fouls and not a lot of action.

Okazawa jumped out to an early lead, with Krishan fighting in his usual mauling, ugly matter. It was a surprising tactic considering he was far more dominant in a previous tournament win over Okazawa to qualify for Tokyo. 

Krishan was warned for separate fouls in round two, though not to where he was deducted a point. He did suffer a standing eight count in the third and final round as he exits the Olympics for the third and final time.

Okazawa has a tough challenge ahead, as he next faces Cuba's Roniel Iglesias who enters his fourth Olympic competition. Iglesias won Gold in 2012 London and Bronze in 2016 Rio.

Albert Mengue (Cameroon) posted the first stoppage of Tokyo 2020 competition, as he halted Thabiso Dlamini (Eswatini) in the third and final round in the Round of 32 competition at welterweight Saturday afternoon in Tokyo.

Mengue was ahead 20-18 on all three scorecards by the time the referee intervened to stop the contest at 2:35 of round three. With the win, Mengue goes to the Round of 16, where he faces number-Ireland's Aiden Walsh on Tuesday, July 27.

Merven Clair (Mauritius) has already enjoyed more success than was the case during his appearance in the 2016 Rio Olympics. The 28-year-old Mauritian had his way in a three-round unanimous decision win over Wyatt Sanford (Canada).

Four of the five judges awarded a 30-27 shutout win to Clair, while the judge from Ukraine scored the contest 29-28. Clair will next face number-four seed Zeyad Ishaish (Jordan) on Tuesday, July 27.

Aliaksandr Radzionau (Belarus) proved to be too much for Necat Ekinci (Turkey), prevailing by split decision.

Ekinci—who suffered a cut in round two and lost one point in round three—won by scores of 29-27 on two scorecards, with Radizionau winning by the same score on the three remaining cards to advance to the Round of 16. Radzionau has a tough task ahead of him, as he faces number-one seed Pat McCormack (Great Britain) on Tuesday, July 27.

Jake Donovan is a senior writer for BoxingScene.com. Twitter: @JakeNDaBox