No elevator ride for Juan Martin del Potro this time, understandably. Just another victory in Olympic tennis for the guy who knocked off No. 1 Novak Djokovic.

A day after getting stuck for 40 minutes in an athletes village elevator before upsetting Djokovic in the Rio de Janeiro Games tournament's first round, del Potro was back on court Monday.

No rest for the weary.

Still, he produced a 6-3, 1-6, 6-3 victory over Portugal's Joao Sousa with the help of 16 forehand winners, each more thunderous than the last.

"It was really hard for me," del Potro said about the quick turnaround. "I could not believe my match from yesterday, and I already won another match."

And he had a doubles match to go get ready for later Monday, too.

The win over Sousa started only 15½ hours after the oft-injured del Potro, whose ranking is outside the top 100 after a series of wrist operations, finished beating Djokovic in straight sets Sunday night, then wept on court.

Earlier that day, the 6-foot-6 Argentine found himself trapped while trying to get from one floor to another — until getting rescued by countrymen competing in handball.

Asked if he took an elevator before facing Sousa, del Potro replied with a laugh: "Not today."

In a tournament that began without half of the members of the ATP's top 10 — including Roger Federer and Stan Wawrinka — del Potro is suddenly looking like someone who might be able to add another medal to the bronze he took home from the 2012 London Olympics.

Because of injuries, del Potro had gone 2½ years without participating in a Grand Slam tournament until playing at Wimbledon, so one big question is what his fitness level is.

"I'm getting better. I'm in good shape, but I don't know if I'm prepared to play six or more matches," he said. "This week I'm just going slowly, trying to get better every day."

One of these men will be a semifinalist in his portion of the bracket: del Potro, Spain's 10th-seeded Roberto Bautista Agut, Japan's Taro Daniel or Luxembourg's Gilles Muller, who advanced to the third round Monday by eliminating fifth-seeded Jo-Wilfried Tsonga 6-4, 6-3. Tsonga, who is from France, was treated by a trainer for a problem with his right foot.

A day after Djokovic and two other No. 1 seeds were beaten — including Serena and Venus Williams in women's doubles — things were far quieter Monday afternoon. Defending gold medalist Serena was to play her second-round singles match against France's Alize Cornet at night.

Among the women moving into the third round: No. 2 Angelique Kerber of Germany, No. 7 Madison Keys of the U.S., No. 8 Svetlana Kuznetsova of Russia, No. 9 Carla Suarez Navarro of Spain, and No. 10 Johanna Konta of Britain.

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