Rio Olympics: Juan Martin del Potro Keeps 2016 Games Dream Alive

Juan Martin del Potro followed up his shock 2016 Rio Olympics defeat of Novak Djokovic by downing Portugal's Joao Sousa on Monday in front of a legion of passionate, vocal Argentine fans.

The giant 27-year-old, ranked at 141 in the world after years of wrist injury misery had pushed him to the brink of quitting, swept to a 6-3, 1-6, 6-3 win.

He goes on to face Japan's Taro Daniel where he will start favourite, especially if he again musters the support of the fans who turned centre court into a little corner of Buenos Aires on Monday.

Dressed in sky blue football shirts, they draped national flags and banners over the barriers and responded defiantly when locals booed the mention of del Potro's name.

"It was really hard for me. I cannot believe my match from last night and I already won another match at the Olympics," said the 2009 US Open champion.

"I'm very glad with my success. I played really well at the end of the match and I think that was the key."

Del Potro did not face a break point in his opening win over Djokovic.

But the emotion of the previous night looked to have cost him when world number 36 Sousa broke twice in the second set to level the tie.

Del Potro kept his nerve, however, and carved out a key break in the sixth game of the decider before clinching a place in the last-16 on his third match point.

Things got even better for Del Potro moments later when French fifth seed Jo-Wilfried Tsonga, a potential quarter-final opponent, lost 6-4, 6-3 to Gilles Muller of Luxemburg.

Casualties

Meanwhile, the Olympic Games casualty count keeps creeping up.

German 13th seed Philipp Kohlschreiber was forced to pull out with a broken foot, handing Slovakia's Andrej Marti a walkover into the third round.

Romania's Monica Niculescu gave a walkover to Russia's Svetlana Kuznetsova due to a lower back injury.

The women's draw had also to find four last-minute replacements for the first round.

Hsieh Su-wei of Taiwan withdrew after a row with her federation and was replaced by Lucie Hradecka of the Czech Republic.

Romania's Andreea Mitu was slotted in at the last minute when Jelena Jankovic pulled out with a shoulder injury.

Ukraine's Lesia Tsurenko was replaced by Aleksandra Krunic of Serbia, while Galina Voskoboeva gave way to Kazakh compatriot Yaroslava Shvedova.

In the men's event, Dustin Brown of Germany and Andrey Kuznetsova of Russia were injured and retired from their first round matches on Sunday.

On Monday, it was the turn of Lucie Safarova of the Czech Republic to quit early when she retired from her match with Kirsten Flipkens of Belgium after dropping the first set.

German second seed and Australian Open champion Angelique Kerber recovered from a 4-1 first set deficit to defeat Canada's Eugenie Bouchard, 6-4, 6-2.

It was Kerber's first win over the 2014 Wimbledon runner-up in three years.

Kerber next faces Australia's Samantha Stosur who was too strong for Misaki Doi of Japan, winning 6-3, 6-4.

There was also an early win for two-time Wimbledon champion Petra Kvitova over Danish flag-bearer Caroline Wozniacki 6-2, 6-4.

US seventh seed Madison Keys came out on top in a three-hour duel against Kristina Mladenovic of France 7-5, 6-7 (4/7), 7-6 (7/5).

Martina Hingis, playing in her first Olympics in 20 years, teamed up with Timea Bacsinszky to reach the women's doubles second round.

The Swiss pair defeated Coco Vandeweghe and Bethanie Mattek-Sands of the United States 6-4, 6-4.

Later Monday, defending women's champion Serena Williams, chasing a fifth gold medal, takes on Alize Cornet of France.

Cornet defeated the American star three times in 2014 including at Wimbledon.

Japan's Kei Nishikori meets Australia's John Millman who created history in the first round when he recorded the first 'double bagel' 6-0, 6-0 win in Olympic history.

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