"We didn't deal well with some details in the first half and conceded many errors," added the Chinese international.
Han Ziqi contributed a game-high 23 points, but her solo effort could not save Tianjin from a big loss.
The Spaniard, who is seeking his 13th title at Roland Garros, defeated Sinner 7-6 (7-4), 6-4, 6-1 to set up a rematch with Diego Schwartzman on Friday.
The "Eisernen" made a perfect start on home soil as Christopher Lenz tested Mainz goalkeeper Robin Zentner in the early stages, before Max Kruse nodded home his debut goal after Sheraldo Becker's pinpoint cross to the far post in the 13th minute.
Dongguan scored 10 points in a row early in the first quarter, before Zhejiang responded with the same scoring run through consecutive layups and foul shots, leading 20-17 at the end of the quarter.
Roma had a shaky start to the new season, managing only one draw and one defeat after two rounds.
It was also the 96th victory at Roland Garros for the Spaniard, who is seeking a 20th Grand Slam title to equal Roger Federer's record.
ABUJA, Oct. 5 (Xinhua) -- Nigeria on Monday appointed American Randy Waldrum as the new head coach of the women's national football team, also known as the Super Falcons.
The second set was filled with breaks as both players failed to hold their serves from the sixth to the 11th game. Zhang served to win in the 10th game but was broken by her French opponent. However, when the chance appeared again on the 12th, Zhang didn't miss it and wrapped up the victory with a flawless love game.
Inner Mongolia tamed Hebei by 44 points on Friday. Center Li Yueru shot 10 of 12 from the field to finish with a game-high 21 points. Chen Liyu helped with 16. Wei Wei nailed 14 points off the bench.
Temwa Chawinga gave Wuhan a 1-0 lead in the 10th minute as she received a pass and rifled an effort into the net. Shanghai leveled the game in the 13th minute as Banda stole the ball from a Wuhan defender in the penalty area and slotted it past the goalkeeper. Just one minute later, Shen Mengyu's goal, from an assist from Banda, helped Shanghai gain a 2-1 lead.