Tim Henman overcame a back injury to battle past 6ft 10in Croatian Ivo Karlovic in five sets at the US Open.
Henman admitted he had almost not made it on to court because of the injury, but fought his way to a 7-6 (7-2) 6-7 (7-9) 4-6 6-4 6-4 victory.
He could have made it an easier afternoon when he had five points for a two-set lead, but Karlovic forced Henman into a fifth set.
The Briton will play Frenchman Jerome Golmard in the second round.
"It was a tough match all round," said Henman afterwards. "There had been talk about my back but I had a great practice on Saturday and felt 100%.
"But it totally seized up on Saturday evening; I couldn't walk and it felt like someone was sticking a knife in my back, so I spent a couple of days working on it.
"It improved massively in 48 hours."
And Henman revealed that his coach, Paul Annacone, had asked tournament officials to reschedule his match for fear that the fifth seed would not be fit on Monday.
"I've got to thank the Order of Play Committee," said Henman, "because I was down to play on Monday but Paul had a word with them and said 'any chance of a Tuesday?'"
And the British number one is optimistic that he will be in better shape when he takes on Golmard, probably on Thursday.
"I can only improve physically, I feel like been serving pretty well. I'm pleased to get through this, I didn't know if I was going to play.
"I haven't seen (Golmard) for a while, he's struggled with injury. He's a lefty with an awkward game, he's come through qualies, but if I progress physically I've got a good chance."