American teenager Coco Gauff says sports stars should use their platform to drive social change and called for peace and an end to gun crime after reaching the French Open final.
The 18-year-old wrote the message on a television camera after she reached a first Grand Slam singles final.
"It felt right in the moment. Hopefully it gets into the heads of people in office to change things," said Gauff.
Last week, 19 children and two teachers were killed by a gunman in Texas.
On Thursday, a gunman killed three employees and a patient at an Oklahoma hospital.