The system has become commonplace in recent years on the other surfaces but clay events had largely persisted with line judges and the umpire coming down from his or her chair to examine the mark left by the ball when calls were contested.
There were also doubts over the accuracy of the electronic system given the way clay moves, but this season line judges have been removed from all events on the ATP Tour and many on the WTA Tour.
Predictions that this could prove problematic have played out, with top seed Zverev the latest player to be left incensed by a call during his 2-6 7-6 (7-3) 7-6 (7-0) victory over Spain's Alejandro Davidovich Fokina in the third round in Madrid.
On the first point of the 10th game in the second set, and moments after his opponent had contested a call, Zverev was convinced a backhand from Davidovich Fokina had landed wide, telling umpire Mohamed Lahyani there was a "malfunction in the system" after it was called in.
When his protestations came to nothing, Zverev took his phone out of his bag and snapped a picture of the mark, earning himself a warning from Lahyani for unsportsmanlike conduct.
The German later put the picture on Instagram accompanied by the caption: "Just gonna leave this one here. This was called in. Interesting call."
Referring to the picture on the social media site X, world No.21 Donna Vekic wrote: "So crazy that umpires are not able to overrule this! Insanity."
World No.1 Aryna Sabalenka had experienced the same situation in Stuttgart earlier this month, while Victoria Azarenka posted an image of a call from another Madrid match on social media.
The French Open so far remains an outlier and will continue with line judges for next month's tournament.
Elsewhere in the Spanish capital, defending champion Andrey Rublev lost 6-4 0-6 6-4 to Alexander Bublik and will tumble out of the world's top 15 as a result.
Third seed Taylor Fritz was level at one-set all with Benjamin Bonzi when the Frenchman retired through injury, while Daniil Medvedev defeated Juan Manuel Cerundolo 6-2 6-2.
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