Victorious Elina Svitolina wears black ribbon for Ukraine at Wimbledon
Shortly after setting up a showdown with 2022 champion Elena Rybakina with her 6-2, 6-1 victory over China's Wang Xinyu, Svitolina burst into tears in her on-court interview.
"It's a difficult day for Ukrainian people," said Svitolina, before breaking down.
The Odesa-born player told reporters that she had wanted to stay in her room and deal with her emotions.
"When you have these sad days where you don't want to do anything, it was this kind of day for me," Svitolina said.
"It's difficult really to explain, I guess, because for us Ukrainians, it's very close to our heart and a very sensitive topic, very sensitive emotions that we feel every single day.
"But today was one of the days where it was even more difficult because the missile landed on the kids' hospital. Straightaway you see images and everything that happened."
Russia hit the children's hospital with a missile in broad daylight and rained missiles down on other cities across Ukraine, killing at least 36 civilians in the deadliest wave of air strikes for months.
The Russian Defence Ministry said its forces had carried out strikes on defence industry targets and aviation bases in Ukraine. Moscow has repeatedly denied targeting civilians and civilian infrastructure.
Svitolina, the 21st seed, who last year matched her best run at the grass-court Grand Slam by reaching the semi-finals, wore a black ribbon on her white top on Monday.
"It's been approved by Wimbledon today," said Svitolina, who still has family in Ukraine. "I feel it would be understandable after such a big attack on my country."
Svitolina said she was motivated to do well and raise awareness about the war.
"I'm playing such an amazing event ... I have to think about how I can use that in a way for Ukrainian people," she said.
"My win today, it was a small light that brought a happy moment for Ukrainian people. I got so many messages. The people are thankful for my performance.
"It brings me a lot of, let's say, joy in a way on this sad day."
Wimbledon last year lifted a ban on Russian and Belarusian players, allowing them to participate as "neutral" athletes in a climbdown from the stance it took in 2022, after the invasion.
Svitolina said she would prefer things to go back to how they were at the grass-court Grand Slam two years ago.
"For now, I want to raise awareness, raise funds for people in need and raise support for kids through my foundation," she said