American player Taylor Townsend said former French Open champion Jelena Ostapenko told her she had "no class" and "no education" in a heated US Open row.

Tension between the pair escalated after a net cord went in Townsend's favour during a 7-5, 6-1 second-round win - and 25th seed Ostapenko accused her of not apologising.

The pair had a curt handshake after Townsend clinched victory before Latvian Ostapenko made a comment at the net.

Both players continued to express their views in an animated argument at Ostapenko's chair.

Asked what happened at the net, Townsend said: "She told me I have no education, no class, and to see what happens if we play each other outside of the US.

"I said, I'm excited, bring it on."

On-court microphones picked up 29-year-old Townsend telling Ostapenko to "take the L (loss)".

Townsend, the world number one doubles player, then whipped the crowd into a frenzy by celebrating with them wildly.

Boos rang around Court 11 as Ostapenko departed.

"There's no beef," added Townsend.

"But I didn't back down because you're not going to insult me, especially after I carried myself a certain type of way, with nothing but respect.

"If I show respect to you, I expect respect as well. That's just the fact of the matter."

Ostapenko, 28, is well-known for allowing her frustrations to spill over and has previously received fines for unsportsmanlike conduct.

Afterwards, she posted a message on Instagram accusing Townsend of being "very disrespectful".

"I told my opponent she didn't say sorry, but her answer was that she doesn't have to say sorry at all," Ostapenko, who won the Roland Garros title in 2018, wrote.

"There are some rules in tennis which most of the players follow and it was the first time ever that this has happened to me on tour.

"If she plays in her homeland it doesn't mean she can behave and do whatever she wants."

Townsend said she did not expect to receive an apology from Ostapenko.

"Saying I have no education and no class, I don't really take that personally, because I know that it's so far from the truth," Townsend said.

"If I allow what other people have to say about me affect me in that way, then they win."

Townsend, an African-American, was also asked if she thought there was a racial undertone to Ostapenko's comments.

"I didn't take it in that way," Townsend said.

"But also that has been a stigma in our community of being not educated, and all of the things, when it's the furthest thing from the truth.

"Whether it had racial undertones or not, that's something she can speak on."

Ostapenko posted again on Instagram later on Wednesday to deny her comments had a racial element.

"I was never racist in my life," she wrote. "I respect all nations of people in the world, for me it doesn't matter where you come from."