RIO DE JANEIRO — Tennis star Serena Williams is headed home.

The top-seeded player in the women’s tennis tournament at the Rio de Janeiro Olympics got upset on Tuesday by Elina Svitolina of Ukraine, deprived of a chance to defend the gold medal she won four years ago in London.

Williams looked out of sorts and irritated, shanking shots from side to side. She had five double-faults in one game alone in the 6-4, 6-3 loss to the 20th-ranked Svitolina.

Williams wiped her forehead, picked up her rackets and headed back quickly to the locker room. Svitolina, who had never played in an Olympics, smiled and stuck her arms out in front of her, palms up, as if waking up from a dream.

Svitolina had won 63 points, but just nine from clean winners. The others came thanks to Williams’ 37 unforced errors and 17 forced errors.

Other highlights from Day 4 at the Rio Games:

MEDAL STRIPPED: A Ukrainian javelin thrower was stripped of his silver medal from the 2012 London Olympics, becoming the latest athlete disqualified after the retesting of stored doping samples. Oleksandr Pyatnytsya tested positive for the steroid turinabol and was retroactively disqualified from the London Games and ordered to return his medal, the International Olympic Committee said.

GRIEVING COACH LEADS U.S.: Adam Krikorian returned to the pool deck for his first game since his brother’s sudden death last week to coach the U.S. to an 11-4 win over Spain in water polo. Maggie Steffens, Courtney Mathewson and Kiley Neushul scored two goals apiece, and Ashleigh Johnson had 11 saves while becoming the first black woman to play water polo for the U.S. in the Olympics.

RUGBY STUNNER: Sonny Bill Williams was helped off with an ankle injury during New Zealand’s shocking 14-12 loss to Japan in its first game of rugby sevens. New Zealand is a 12-time world series champion and one of the top contenders for the first rugby medals awarded at an Olympics in 92 years.

JUDO HISTORY: Hungarian-born Szandra Szogedi made history when she stepped onto the judo mat to become the first judoka to represent Ghana – she obtained citizenship through her husband. But facing Brazilian Mariana Silva in the first round, Szogedi had to deal with a crowd shouting support for her opponent. After less than two minutes, the fight was over: Silva took Szogedi down and caught her in a stranglehold. Afterward, a tearful Szogedi said she was “gutted.”

PELE IMPROVING: Pele tweeted that he hopes to appear at the closing ceremony after missing the opening because of his health. The soccer great was the organizers’ preferred choice to light the cauldron, but first cited sponsorship commitments and later health concerns for staying away.

WORLD-RECORD LIFT: Deng Wei won Olympic gold and set a world record in women’s weightlifting, hoisting 147 kilograms in the clean and jerk and 115 in the snatch for a total of 262. Her clean and jerk lift also broke her world record by 1 kilogram.