When you're losing 0-6 0-5 and facing match point, the chances are there is no way back.
But the old saying goes that winners never quit - and Tara Moore refused to give up when she found herself in that exact position on Tuesday.
In a show of extraordinary grit, the British number nine saved herself from being double bageled at 30-40 down, and went on to beat French third seed Jessika Ponchet 0-6 7-6 6-3 at the ITF World Tour event in Sunderland.
The greatest comeback in tennis history? Well, the 26-year-old said on social media that it had been "never in doubt".
Moore has won nine ITF singles titles and reached the second round of Wimbledon in 2016.
She will face either Germany's Yana Morderger or Romania's Elena-Teodora Cadar in the second round in Sunderland.