Play was canceled at the Madrid Open on Monday following a massive power outage in the Spanish capital.
ATP Tour and WTA Tour matches were underway when the electricity went out at about 12:30 p.m. local time.
The blackouts affecting parts of Spain and Portugal prevented the use of electronic line calling systems. Following a delay of several hours, the decision was made to cancel the rest of the day's schedule.
"For reasons beyond the control of the organization and in order to guarantee general safety, the nationwide power-cut experienced in Spain on Monday 28 April has forced the cancellation of both the day and night sessions at the Mutua Madrid Open," organizers announced on social media.
A "spider cam" was left dangling over the court at Manolo Santana Stadium, where 15th-seeded Grigor Dimitrov of Bulgaria was leading Britain's Jacob Fearnley 6-4, 5-4 in the third round when play was suspended.
In singles competition, only one men's match and two women's matches were completed before the interruption.
Italy's Matteo Arnaldi advanced to the fourth round with a 6-3, 6-4 victory against Damir Dzumhur of Bosnia and Herzegovina. Arnaldi saved all five break points he faced and struck six aces to win in 1 hour and 45 minutes.
On the women's side, seventh-seeded Russian Mirra Andreeva and fourth-seeded Coco Gauff won their fourth-round matches before the action was halted.
Andreeva defeated Ukrainian qualifier Yuliia Starodubsteva 6-1, 6-4, and Gauff was a 6-4, 6-2 winner against Switzerland's Belinda Bencic. Andreeva and Gauff will meet in the quarterfinals.
Andreeva was serving for the match when the power went out.
"It was 15-40 on my serve," Andreeva later told reporters. "I was like, 'Oh, Mirra, please -- please -- do everything in your power to take this game and finish the match. Because I knew that if it would go to 5-5 probably we would have to wait and I would be here yet."
Gauff was in the middle of her on-court interview when the microphone died.
"It was pitch-black, and I got the gist that the power went out," Gauff said. "I thought it was just us and then I realized it was the whole country -- that's just insane."
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