Wellington - Feliciano Lopez, playing his second match of the day, knocked top seed and world No 12 Fabio Fognini out of the ATP Auckland Classic on Wednesday to advance to the quarter-finals.
The 38-year-old Spaniard, one of several players forced to double up following the rain disruption the previous day, was forced to play three sets to survive both matches and spent four hours 25 minutes on court with only a three-hour break in the middle.
He began the day beating Pablo Andujar 3-6, 7-6 (7/4), 6-4, and after a three-hour rest he came from behind to beat Fognini 3-6, 6-4, 6-3.
The 61st ranked Lopez believes the rain delay did him a favour.
"The first match was tough but I honestly think it was very helpful for me (before playing) against Fabio," Lopez said.
"It was my first match this year, it was two and a half hours on the court so that was very helpful for me and without that match I don't think I could have played the way I did against Fabio."
Lopez will face Poland's Hubert Hurkacz in the quarter-finals after the sixth-seed put away Mikael Ymer of Sweden 6-2, 7-6 (7/2).
Fourth seed and two-time Auckland champion John Isner, who had a first-round bye, opened his campaign with a three-set win over defending titleholder Tennys Sandgren and snapped their tie-break history along the way.
Isner, the tournament fourth seed, won 7-6 (7/3), 6-7 (7/1), 6-3, pulling away in the deciding set with the first service break of the match when Sandgren faltered at 2-2.
Until then the pair had only been separated by tie-breaks with Isner taking their previous encounter in Stockholm two years ago in three tie-break sets.
"I feel good about that," Isner said of finding a way around Sandgren's serve and dishing up 16 aces of his own.
After losing all three of his matches last week at the ATP Cup in Australia, Isner was relieved to register a win.
"The freshest memory I have right now is winning and playing a good third set, so I have to use that to gain momentum going forward," he said.
"I won a tie-breaker, he won a tie-breaker, there wasn't much separating us at all.
"Eventually I played a good game at 2-2 in the third and was able to break and give myself some momentum. It's a good sign."
In the quarter-finals he will play the winner of the second-round match between Kyle Edmund and Andreas Seppi.