Third seed Marin Cilic let a two-set lead slip as he was knocked out in the second round of Wimbledon by Argentina's Guido Pella.
Last year's beaten finalist was well in control before rain halted proceedings on Wednesday evening.
But, on the resumption, Pella improved and wrapped up the third set and took the fourth on a tie-break.
And the world number 82 held his nerve to convert his fourth match point and win 3-6 1-6 6-4 7-6 (7-4) 7-5.
It is the biggest win of Pella's career and he is now in the third round of a Grand Slam for the first time.
"The rain coming helped me a lot," the 28-year-old, who had not won a match at Wimbledon in his two previous visits before this year, told BBC Sport.
"Yesterday he was playing so, so well and I couldn't do anything.
Pella was playing in a five-set match for only the eighth time
"Today, I started to play more aggressively and fight for every ball and that is why I won.
"Grass isn't my favourite surface but I started to feel more confident and served a lot better."
On Friday, Pella will play American world number 103 Mackenzie Mcdonald who will also be making his first appearance in the last 32 of a major.
"Every time you win a match in a Grand Slam it is a good feeling," he added.
"Tomorrow is a different match and we will both have pressure so it will be a tense match but I will try to be calm and win."
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