Kurt Walker (Ireland) delivered arguably the biggest upset of the 2020 Tokyo Olympics to date, following a split decision win over number-one seeded featherweight Mirazizbek Murzakhalilov (Uzbekistan).

Walker overcame cuts over both eyes to prevail on four of the five judges. Mirzakhalilov won 30-27 on one card, overruled by scores 29-28 on each of the remaining four cards Wednesday afternoon at Kokugikan Arena in Tokyo.

Speed proved key for Walker, who sprinted out to an early lead. Mirzakhalilov picked up the pace at the start of round two, briefly stunning Walker but unable to stay on the attack to the point of producing a much needed 10-8 round. In fact, it was Walker who—through a mid-round rally—managed to steal the frame on three of the five scorecards.

Owning a commanding lead heading into the final round, Walker just needed to remain upright in order to prevail. Mirzakhalilov never stopped coming forward, managing to draw cuts over both eyes of Walker. What he couldn't produce was that one shot to end the fight prior to the bell as the number-one seed falls in the quarterfinal round. 

Of concern to Walker and the Ireland Olympic boxing team is whether either of his cuts will pose a threat to his being ready for the quarterfinal round. The good news is that he has four days to fully heal. 

Assuming he's fit to fight, Walker will face USA's Duke Ragan who turned away Kazakhstan's Serik Temirzhanov via unanimous decision to advance. Full recap of Ragan's win can be found here: https://www.boxingscene.com/duke-ragan-beats-serik-temirzhanov-advances-featherweight-quarterfinals--159436

Samuel Takyi (Ghana) outlasted Jean Carlos Caicedo (Ecuador) to claim a well-earned unanimous decision in a terrific slugfest. A strong final round surge propelled Takyi to victory, winning on all five scorecards (30-27, 29-28, 29-28, 29-28, 29-28).

With the win, Takyi is the first Olympic boxer from Ghana to advance to the quarterfinals since the late Alfred Kotey in 1988. Kotey—who passed away last June due to complications with COVID—was unable to perform in his quarterfinal matchup with Cuban legend Mario Kindelan and lost by walk-over, though went on to win a WBO bantamweight title. 

Takyi will next face Ceiber David Avila (Colombia), who claimed a split decision win over Everisto Mulenga (Zambia). Avila won by scores of 30-27, 30-26, 29-27 and 29-28, with Mulenga claiming a 29-28 nod on the lone card in his favor. 

Lorenzo Alvarez officially begins his quest for a third straight Olympic medal. The two-time Bronze medalist enjoyed a quick start to his run, forcing a referee stops contest (RSC) Daniyal Shahbakhsh (Iran) midway through round two. 

The bout was all one way, with Alvarez establishing his dominance early. His sharp punching drew a cut, which Shahbakhsh's corner was unable to control. The wound was deemed too severe to continue, though forcing the stoppage at 1:45 of round two. 

Alvarez will next face Chatchai Butdee (Thailand), a three-time Olympian who'd previously never advanced beyond the Round of 16. Butdee has now made it to the quarterfinals following a split decision win over Mirco Jeheil Cuello (Argentina). Scores were 29-28 on all five cards, one for Cuello and four in favor of Butdee who helps run Thailand's record to 5-1 so far in Tokyo. 

Tsendbaatar Erdenebat (Mongolia) and Albert Batyrgaziev (ROC) both needed big finishes in order to advance to the next round.  

Erdenebat fended off a stiff challenge fro van Duong Nguyen (Vietnam) to prevail by scores of 30-27 x4 and 29-28. Errdenebat will now return to the quarterfinal round, having reached that point in 2016 Rio only to be sent home by eventual silver medalist Shakur Stevenson. 

Batyrgasiev retained his number-two ranking, avoiding the upsets that occurred earlier in the day following a decision win over Alexey Miguel de la Cruz (Dominican Republic). 

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