The controversial act of 'gamesmanship' that left Federer fans fuming

Stefanos Tsitsipas caused controversy in his shock win over Roger Federer with a questionable tactic at a very crucial moment.

Federer’s quest for a record seventh Australian Open title came crashing to a dramatic halt with a shock fourth-round loss to Greek prodigy Tsitsipas.

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In a scintillating contest on Rod Laver Arena on Sunday night, 37-year-old Federer could not overcome his 20-year-old opponent who claimed a 6-7 (11-13) 7-6 (7-3) 7-5 7-6 (7-5) victory to continue his magical run at Melbourne Park.

The match was not without its controversy, with both men agitated by a number of umpiring calls.

Tsitsipas left Federer fuming with a controversial act. Image: Getty

And Tsitsipas was on the receiving end of a raft of criticism late in the match when he called a medical timeout in a move that many thought was a tactical ploy.

Up 4-3 in the fourth set, the young Greek called for the trainer a good 10 minutes before he actually came out onto court, leaving Federer questioning the umpire as to whether or not Tsitsipas was legitimately injured.

The trainer proceeded to rub Tsitsipas’ lower legs, seemingly treating him for cramp – an ailment that umpires do not usually allow medical timeouts for.

Stefanos Tsitsipas receives medical attention. (Photo by DAVID GRAY/AFP/Getty Images)

TV commentators suggested Tsitsipas was only calling for the trainer to get a breather and disrupt Federer’s rhythm, a line of thought reflected on social media.

Tsitsipas then appeared to flout the rules again when he took his time returning to the court after the treatment.

Having already received two time violation warnings, John McEnroe felt he should have been hit with a point penalty.

“The umpire, I think, was lenient there,” Todd Woodbridge said in commentary.

“It was just a normal changeover and he took a lot longer.”

To his credit, Federer played down the controversy in his post-match press conference.

“It’s human and it’s part of the game,” Federer said of the umpire controversies.

“I’m not going to start complaining about linesmen or umpires.”

The 14th-seeded Tsitsipas will now face Spain’s Roberto Bautista Agut in the quarter-finals and could meet Rafael Nadal in the final four.

with AAP