Eighth-seeded Elina Svitolina advanced to the third round at Wimbledon after Margarita Gasparyan had to retire with a leg injury in the second set.
Gasparyan was leading 7-5, 5-6 when she was forced to quit.
Gasparyan had been on the verge of an upset, two points from the match at 5-4 in the second, but Svitolina held and her opponent was then injured after delivering a serve at 0-15 in the next game.
She clutched her left thigh in pain and then remained lying on the baseline for several minutes.
Svitolina showed her class by bringing water to her fallen rival and comforting her at the baseline, as she waited for the physio to arrive — while the crowd on Court No. 3 watched on in stunned silence.
Gasparyan has had three surgeries on her left knee since her last Wimbledon appearance in 2016.
"Honestly, I was a little bit shocked," Svitolina said of Gasparyan's problems. "It's never nice to get this when someone is injured like that. It puts you a little bit off.
"At the end we'd expect that she would go and play. Yeah, it happened that way and really unfortunate for her.
"You give her some water, because I know when there is cramps you need to drink lots of water. Your muscles are contracting, so it's important just to drink lots of fluids.
"So that's why I gave her some water, because no one really did anything. I mean, we were trying to help, but, yeah, it's tough to react straight away."
Gasparyan eventually got back up but was broken and then retired during the next game.
- AP, with news.com.au