INDIAN WELLS, Calif. — The Ukrainian teenager Marta Kostyuk and the Belgian veteran Maryna Zanevska played for more than three hours in the sun and a swirling wind.

They played through pain and concern about issues much larger than tennis, and when they met on the same side of the net after Kostyuk’s victory, 6-7 (5), 7-6 (6), 7-5, in the opening round on Thursday, they shared a long, tearful embrace and a similar message.

“I told her that everything is going to be all right,” Zanevska said.

“I told her that everything is going to be OK, that our parents are going to be OK,” Kostyuk said.

Indian Wells is a 10-hour time change and more than 6,000 miles away from the Ukrainian capital of Kyiv, where Kostyuk was born, and from the Ukrainian port city of Odessa, where Zanevska was born before immigrating to Belgium in her teens and leaving her relatives behind.

But Ukraine’s war with Russia, now into its third week, still feels inescapably close to the Ukrainian players competing at the BNP Paribas Open.

“It’s just terrifying,” said Kostyuk, 19, one of tennis’s brightest young talents. “Especially in the beginning, the first couple days, my whole family was there. They were all in one house, so if anything was about to happen, I would lose the whole family. So, thinking of it is just you go to sleep and you don’t know if you wake up the next morning having the family.”

She continued: “I’m coping the way I’ve been coping. Everyone is different. I chose to fight. I came here. At the beginning, I was feeling guilty that I’m not there. You know, the whole family is there but not me. I was feeling guilty that I’m playing tennis, that I have the sky above me that is blue and bright and very calm and mixed feelings. But you can’t be in this position, because everyone is fighting how they can fight, and my job is to play tennis, and this is the biggest way I can help in the current situation.”

Russian players are in Indian Wells, too, but while Kostyuk played with Ukraine next to her name in the draw and on the scoreboard, the Russians and the Belarusian athletes, whose country has cooperated with Russia’s attack on Ukraine, are playing without national symbols or identification, as mandated by the men’s and women’s tours.

Ukraine’s biggest tennis star, Elina Svitolina, lobbied successfully for that policy before she agreed to play Russia’s Anastasia Potapova in a match at the tournament in Monterrey, Mexico, earlier this month. But Kostyuk believes Russian players should be barred from competing on tour altogether, even as individuals.

“I don’t agree with the action that has been taken,” she said. “Look at the other sports. Look at the big sports, what they did.”

Russian and Belarusian athletes were banned from the Paralympics in Beijing, and Russian national teams and clubs have been banned from major global sports like soccer and basketball. But though Russian and Belarusian track and field athletes have been barred from major competitions like this year’s world outdoor championships in Eugene, Ore., individual Russian athletes are still allowed to compete internationally for their non-Russian clubs in, for example, European soccer leagues and the N.H.L.

Daniil Medvedev, the Russian men’s star who recently displaced Novak Djokovic atop the rankings, acknowledged that “there is always a possibility” that Russian tennis players could be banned altogether.

“We never know,” Medvedev said in Indian Wells on Wednesday. “The way the situation is evolving in other sports, some sports made this decision, especially the team sports.”

But for now, tennis has taken a comparatively moderate approach, although this year’s men’s and women’s tour events in Moscow have been canceled and Russian teams have been barred from the Davis Cup and Billie Jean King Cup.

“It’s a very tricky thing because I see that all other sports are removing Russians from their competitions,” Zanevska said. “And in the tennis community they did a few steps like removing the flag, and I can imagine it’s tough for the Russian players as well. But really unfortunately, Ukraine needs support as much as possible from all over the world, all the communities, all the types of sports. It counts. I do feel really sorry that the Russian players have to go through this, but the Ukrainian people are going through much worse things.”

The Russian star Andrey Rublev wrote “No war please” on the camera in Dubai last month, and others like Medvedev and the Belarusian women’s stars Victoria Azarenka and Aryna Sabalenka have called for “peace.” But Kostyuk, whose yellow-and-blue tennis outfit here matches the colors of Ukraine’s flag, said she did not like such vague appeals.

“For me ‘No war’ means a lot of things,” she said. “No war? We can stop the war by giving up, but I know this was never an option.”

She added: “These ‘No war’ statements, they hurt me — they hurt me because they have no substance.”

Such sentiments are, nonetheless, too strong for the tournament organizers here. On Thursday, as Kostyuk and Zanevska played in Stadium 6, Wilfred Williams and Mary Beth Williams, American fans, held up a homemade banner that featured two Ukrainian flags and two messages written in Russian: the word “war” with a diagonal line through it and “Let’s go!”

After the match, a tournament official told the Williamses, who are siblings, that they could not continue to display the banner. The BNP Paribas Open does not allow politically oriented signs, although national flags are permitted, and the tournament, in a show of support, has placed Ukrainian flags in its two main stadiums.

“We just love peace and love tennis,” Mary Beth Williams said.

Kostyuk said she had been in Kyiv in late 2013 and early 2014 when a series of protests led to the ousting of Viktor Yanukovych, Ukraine’s pro-Russia president who later fled the country.

“I remember how united everyone was and I remember that we changed the government, and the fact that the guy decided that he thought that finally after eight years we would want to join him, I think, is a very big mistake,” Kostyuk said, referring to Vladimir V. Putin, Russia’s president.

Both Kostyuk and Zanevska, whose parents remain in Odessa, said they were disappointed that Russian players had not expressed regret for the invasion to them directly.

“Unfortunately, none of the Russian tennis players came to me to tell me they are sorry for what their country is doing to mine,” Kostyuk said, emphasizing that the toll on civilians has been particularly heavy in Ukraine. “There was one player who texted me and one player who came by and we had a chat, but I never heard someone’s sorry, never heard that someone is not supporting what is going on. For me this is shocking, because you don’t have to be into politics or into deep stuff to just be a human being.”

Kostyuk said it “hurts” to see the Russian players when she comes to the BNP Paribas Open. “I can’t say anything about Belarusian players, because they are not a part of it,” she said. “They are victims in this, and, all of them, they are trying to be nice. But seeing the players on site really hurts me. Seeing them having the only problem is not being able to transfer the money or stuff, that’s what they’re talking about, it’s like, I don’t know, this is unacceptable for me.”

Kostyuk is one of four Ukrainian women who are playing singles in Indian Wells. The others are the No. 12 seed Elina Svitolina, Anhelina Kalinina and Dayana Yastremska, who fled Odessa shortly after the war began with her 15-year-old sister Ivanna, crossing the border into Romania and leaving their father, Oleksander, and mother, Marina, in Ukraine on the opposite bank of the Danube River.

“My father was telling me, ‘OK, now you have a responsibility on you; it’s your younger sister, and now you have to build your future because you never know how this war is going to end up,’” said Yastremska, 21, in an interview with Tennis Channel on Thursday.

“Now, I understand his words when he said, ‘Now your own war is going to start,’” Yastremska added. “Now I understand how tough it is, how hard it was to cross the border and to see your parents on the other side of the river.”

Yastremska reached the singles final at the WTA event in Lyon last week, and though she lost in the first round of singles in Indian Wells to Caroline Garcia after receiving a wild card, Yastremska and her sister Ivanna were set to compete in women’s doubles on Friday.

Kostyuk will play on, as well, after her draining, emotional victory over Zanevska. Her mother, Talina Beiko, recently left Kyiv to support her daughter on tour. Kostyuk’s father, Oleg, and other family members remain in Ukraine.

Zanevska, despite suffering pain in her back and hip, persevered and served for the match in the third set, but Kostyuk summoned the fortitude to break her at love and sweep the final four games.

Did she do her part for Ukraine on Thursday?

“Yes, because I showed once again what it’s like having a Ukrainian heart and putting everything I can on the court,” Kostyuk said. “And leaving everything out there.”