Table tennis powerhouse China stayed on course to defend both men's and women's singles titles in the 2016 Rio Olympics as its all four players made the quarters, while German star Timo Boll was ousted on Monday.
Men's world No.1 Ma Long came out the most labored Chinese player although defending champions Zhang Jike and Li Xiaoxia who played back-to-back games on a day.
Ma went two sets down in the beginning of his fourth-round encounter in the afternoon against South Korea's 24-year-old sensation Jeoung Youngsik before taking four sets in a row to secure a berth in the last eight.
All other Chinese kept their record clean to reach the quarterfinals without conceding a set. Zhang Jike eased past Chinese Taipei's Chen Chien-An and Romania's Adrian Crisan, and Li Xiaoxia beat Sweden's Li Fen and Lee Ho Ching of Hong Kong, China. Ding Ning ousted Doo Hoi Kem.
Dimitrij Ovtcharov was also tested in his fourth round encounter against Slovenia's Bojan Tokic, beaten 33-31 in the first set in a 11-point format game before rounding it up 4-1.
In the biggest upset on Monday, men's No. 10 seed Timo Boll was knocked out in the last 16 by Nigeria's Quadric Aruna, who became the first African table tennis player ever to make the quarterfinals in Olympics.
Aruna went 3-0 up in sets with fierce attacks before the former world No. 1 found his rhythm to pull two sets back.
It's too late for Boll to turn the tables, however, losing 12-10, 12-10, 11-5, 3-11, 5-11, 11-9.
"It feels so good!" said Aruna, who turns 28 on Tuesday. "It's like a dream come true. I didn't expect to go this far, though I actually believe in myself. Be the quarterfinals is like a miracle to me. I really can't explain what has been going on."
"Timo is amazing. He never gave up, even when I put a lot of pressure on him," he added.
It has been Boll's fifth Olympic Games and the fourth time that the once European "Golden Boy" failed to qualify for the quarters.
"A lot of people were very surprised about Quadric Aruna, not expecting him to play such a high level," said the 35-year-old. "It's also my first time playing him. I really needed a few sets to get control of the game. But finally it was too late."
Boll is Aruna's second big-name victim after the world No. 40 defeated fifth seed Chuang Chih-Yuan of Chinese Taipei in straight sets in earlier rounds.
Named the ITTF's Player of the Year in 2014, Aruna, who trains in Belgium, will face Ma Long late on Tuesday in the quarters.
