Ostapenko and Taiwanese partner Su-wei Hsieh took on Australia's Joint and partner Hao-ching Chan for a place in the women's doubles quarter-finals on Monday.
The fourth seeds beat Joint and Taiwanese Chan 6-4 6-4, but tempers flared after Ostapenko took exception to the behaviour of Chan's mentor.
Hsieh had approached the umpire during a changeover and Ostapenko pointed toward the opposing team's coach, urging the official to intervene.
Ostapenko said the coach had been clapping and shouting after their mistakes, and sarcastically praising their shots in Chinese, which Hsieh translated for her.
"They do this because they know they cannot beat us," Ostapenko told the umpire, calling the behaviour "very disrespectful" and asking for the presence of a Chinese translator.
After the umpire agreed to deal with the situation, the pair returned to the court and turned up the heat to seal the straight-sets win.
Ostapenko then celebrated by roaring toward the opposing box while Hsieh and Chan did not shake hands at the end of the fiery encounter.
Joint and Hao-ching had beaten Venus and Serena Williams 6-3 6-7 (8-6) 7-6 (10-7) in the first round.
Ostapenko, the 2017 French Open singles champion, has been involved in several on-court disputes.
At last year's US Open she accused Taylor Townsend of having "no class" and "no education" in a verbal confrontation with the American.
Ostapenko later apologised, saying her choice of words during the exchange had been misunderstood because English was not her first language.
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