Play was interrupted at the Madrid Open on Monday when a power cut struck the city after world number four Coco Gauff and rising Russian star Mirra Andreeva booked their quarter-finals spots.
A power cut affecting "the whole of the Iberian peninsula and part of France", according to Portuguese electricity network operator REN, halted matches shortly after 10.30am GMT.
On Centre Court, the match between Bulgaria's Grigor Dimitrov and British qualifier Jacob Fearnley was suspended when the Bulgarian was leading 6-4, 5-4 with his opponent serving to stay in the match.
"The outage is preventing the use of electronic line calling systems and also left a spider cam dangling over the court inside Monolo Santana Stadium," the ATP said on its website.
Tournament organisers said on social media they were "working to restore" power "as quickly as possible", without giving a timetable.
Before the cut hit, American Gauff beat Belinda Bencic of Switzerland 6-4, 6-2 in the last 16.
Teenager Andreeva also progressed as she saw of Ukrainian Yuliia Starodubtseva 6-1, 6-4.
When play resumes in Madrid, Stefanos Tsitsipas will take on Lorenzo Musetti and fifth seed Jack Draper is due to play Matteo Berrettini.
A power cut affecting "the whole of the Iberian peninsula and part of France", according to Portuguese electricity network operator REN, halted matches shortly after 10.30am GMT.
On Centre Court, the match between Bulgaria's Grigor Dimitrov and British qualifier Jacob Fearnley was suspended when the Bulgarian was leading 6-4, 5-4 with his opponent serving to stay in the match.
"The outage is preventing the use of electronic line calling systems and also left a spider cam dangling over the court inside Monolo Santana Stadium," the ATP said on its website.
Tournament organisers said on social media they were "working to restore" power "as quickly as possible", without giving a timetable.
Before the cut hit, American Gauff beat Belinda Bencic of Switzerland 6-4, 6-2 in the last 16.
Teenager Andreeva also progressed as she saw of Ukrainian Yuliia Starodubtseva 6-1, 6-4.
When play resumes in Madrid, Stefanos Tsitsipas will take on Lorenzo Musetti and fifth seed Jack Draper is due to play Matteo Berrettini.
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