In one of the most eye-catching clashes to kick off the second week of US Open 2021, Germany’s Alexander Zverev took on the youngster Jannik Sinner. It was a battle of the powerful young-stars on Arthur Ashe stadium. With both players fighting to secure a spot in the last-eight, there were bound to be some fireworks. And there surely were, along with some fiery incidents.

As the match kicked off, both players traded blow for blow. Within no time, the duo boosted themselves into fifth gear. After some pounding ground stroke exchanges and booming serves, it was the Olympic champion Zverev who came clutch when it mattered most. As he claimed the crucial break of serve, he took the first set 6-4. As the packed crowd overlooked, however, a peculiar incident put technology into question.

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Alexander Zverev questions hawk-eye in Round-4 match

With a spot in the quarterfinals on the line, neither player was ready to give in. Over the years, Zverev has come under the radar numerous times for arguing against the on-court calls. Whether manual or electronic, the German has disagreed with decisions on multiple occasions. The US Open fourth round encounter was no different, as the 4th seed was furious and debated against an electronic call.

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Engaging in a good rally, Zverev had the opportunity to close it with an easy volley. However, he narrowly missed it, at least according to hawk-eye. With only electronic hawk-eye functioning this season, the idea of challenges goes out of the window. Yet, the German believed that he in fact made the volley, and argued with the chair umpire regarding the decision of Hawk-eye Live. “I’m not crazy, the mark is in,” quoted an irritated Zverev.

Although the German was shown no respite, the high quality match continued. Will Zverev seal his spot in another Grand Slam quarterfinal? Or does Sinner have other ideas?