GUADALAJARA, Mexico - Imagine coming on for your FIFA World Cup debut on the opening day of the tournament, replacing your nation's captain and, arguably, greatest player of all time.
South Korea had just equalised, eight minutes after falling behind to Czechia in their Group A opener but the win was still up for grabs.
Son Heung-Min, who has shouldered the hopes of an entire country for the past decade or so, had toiled manfully up until that point but had not been enjoying much luck in finding a clear chance in the penalty box.
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So South Korea coach Hong Myung-Bo took a massive gamble. Off went Son, and on came Oh Hyeon-Gyu.
Just 11 minutes after being introduced, Oh saw Hwang In-Beom break down the right and immediately made a darting run to the near post. Hwang's low delivery into the area was dangerous as always, and it was the half-opening Oh needed to send an emphatic first-time finish -- with the aid of a deflection -- into the back of the net for South Korea's 80th-minute winner.
Instantly, and just like many before him, Oh became a national hero overnight.
To call Oh a rising star would not exactly be accurate given he is now 25 and actually onto his third club in Europe. After his breakthrough came with Scottish Premiership giants Celtic, he went on to have a spell in the Belgian Pro League with Genk before arriving in the Turkish Süper Lig with current team Beşiktaş at the start of the year.
His scoring rate in Europe is creditable if not prolific. Twelve goals in 47 games for Celtic. Twenty-two goals in 73 games for Genk. And, thus far, eight goals from 16 matches with Beşiktaş.
Yet, getting opportunities to lead the South Korea line do not always come easy, especially when an icon like Son is obviously still the main man in attack.
Since his first cap in 2022, Oh has had to bide his time. And there has been competition too even for as a back-up, or at times when Son played out wide and there was a vacancy for the spearhead role.
Cho Gue-Sung was viewed as the prime candidate after his heroics at the 2022 World Cup but has endured a wretched run with injury and illness since, while South Korea even turned to the domestic-based Joo Min-Kyu -- who has never played abroad before -- during the Asian qualifiers for the World Cup when they were assessing all No. 9 candidates.
It is, however, telling that when South Korea needed to change things up against Czechia, Hong opted for Oh even with Cho available on the bench. It proved to be a masterstroke and one that a former captain of the Taegeuk Warriors saw coming.
South Korea's 2018 World Cup captain Ki Sung-Yueng enjoyed much longevity in Europe. He had seven full seasons in the Premier League playing for Swansea City, Sunderland and Newcastle United. He also briefly featured in LaLiga with Mallorca.
But he perhaps enjoyed the most success in his first chapter with Celtic, where he won the Scottish Cup and then the league in back-to-back seasons.
Given they share a similar career path, it would not be a surprise if Ki does have a soft spot for Oh. Still, even if that affinity influenced his selection of Oh as the player to watch for South Korea, he was only proven right on the opening day of the World Cup.
"I think Oh Hyeon-Gyu is the best young player at the moment," Ki replied on the eve of the tournament, when asked in an exclusive interview with ESPN which South Korea player could have a breakout World Cup. "He's scored a lot of goals and showed that he can play at a top level, so I think you have to keep an eye on him."
And when asked after his heroics against Czechia how he felt about having been singled out by Ki, Oh was humbled by the praise.
"What can I say? I just can say 'thank you' [to Ki]," Oh told ESPN. "I have to keep pushing in every game, every single day in every training, and I have to show my qualities.
"I'm so happy to get the win [against Czechia]. It means a lot because the first game is always difficult but we managed to win.
"I think winning [the first game] will bring us confidence, and I'm so excited for the next game against Mexico."
It is almost certain that Son will once again start against Mexico on Thursday. A tactical reshuffle also seems improbable given the present system did reap maximum reward against Czechia.
It means that Oh will likely have to wait on the bench for his chance to shine again. Still, his match-winning cameo last week has proven -- if anything -- that the Taegeuk Warriors have others to turn to when things aren't going according to plan. And, longer-term, he has shown what life for South Korea could look like after Son.
Oh could eventually Son's successor as South Korea's attacker-in-chief. At the very least, in the present, he has already proven his ready to make an impact when called upon -- as his team look to build on the positive start they have made at this World Cup.
A former South Korea captain saw it coming all along.