Monica Puig of Puerto Rico reacts after defeating Angelique Kerber of Germany.

Story highlights

Big shock in women's tennis final

Puig wins Puerto Rico's first gold

Beats German second seed Kerber

CNN  — 

First it was Kosovo. Then Fiji got in on the act. On Friday, it was Singapore’s turn.

Now, Puerto Rico has its first Olympic gold medal after tennis player Monica Puig defeated world No. 2 Angelique Kerber of Germany in the women’s singles final.

Ranked 32 places beneath her opponent, Puig dominated the final set with an aggressive display of offensive tennis to round off a deserved 6-3 4-6 6-1 win.

Earlier Saturday, Petra Kvitova of the Czech Republic beat Madison Keys of the US 7-5 2-6 6-2 to claim Rio 2016 bronze.

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‘Si se Puede’

Puig dropped to her knees after securing victory as fans, who had chanted “si se puede” (yes you can) throughout the match, proudly waved Puerto Rican flags in the crowd.

The unlikely triumph also meant Puig became the first unseeded player to become Olympic champion since women’s tennis was reintroduced at the 1988 Olympics in Seoul.

Puerto Rico had won just eight Olympic medals – six bronze and two silver – prior to Puig’s success. Six of those were won in boxing.

After besting two-time Wimbledon champion Kvitova in the semifinals, Puig vowed to win gold for her compatriots back home. “It would mean the world,” she told reporters.

The US territory is $70 billion in debt and has been forced to look towards Washington DC to ease the financial pressure.

Meanwhile, a public health emergency was declared on the Caribbean island by the US Department of Health and Human Services Friday after the rapid spread of the Zika virus there.

CNN’s Don Riddell reported that an emotional Puig entered the press room on her phone later Saturday screaming “Yes, I did it” to the person – believed to be her mother – on the other end.

Addressing reporters shortly after, she said: “It’s just amazing. I know my country really appreciates this and I really wanted to give this victory to them. And the way I did this victory tonight, I wouldn’t want it any other way.”

Delpo outguns Rafa

Meanwhile, Juan Martin del Potro continued his dream run in the men’s singles tournament, reaching the final after an epic clash with 2008 champion Rafael Nadal.

Having upset world No. 1 Novak Djokovic in the first round, the Argentine overcame the Spanish fourth seed 5-7 6-4 7-6 (7-5).

Nadal won doubles gold alongside friend and compatriot Marc Lopez on Friday but fell just short in a gripping final-set tiebreak less than 24 hours later.

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“I am living like a dream,” Del Potro said. “It could be better than (winning the 2009) US Open tournament,” he added, referring to his sole grand slam triumph.

Del Potro will face defending champion Andy Murray in Sunday’s final after the world No. 2 from Great Britain earlier beat Kei Nishikori of Japan in straight sets 6-1 6-4.