Written byAyush Gupta
In what was an intense match, which went until the five sets, Federer lost his cool in the mid-match, as he cursed inside the Rod Laver Arena in Melbourne Park, drawing the sanction.
Here is more.
The incident happened during the third set, when after losing a point, Federer was heard swearing something to himself frustratingly.
Immediately, the linesman, behind him, rushed to chair umpire, Marijana Veljovic, and reported it.
Following the report, Veljovic issued a warning to Federer for 'audible obscenity', leaving Federer shocked.
This led to Federer having a word and arguing with the linesman and Veljovic.
"It was a mix (of languages). Clearly, she speaks mixed. I didn't know that. Next time, I got to check the lines people," said Federer on the incident as he had a work with the linesman.
Speaking further on the incident, Federer feels that especially in crunch situations or matches like Tuesday's, it is normal for a player to say a few words, and believes it was a bit tough.
"It's not like I'm known to throw around words and whatever. It's not like the whole stadium heard it either. But, no problem, I'll accept it," he further said.
The match was off to a fine start for Federer, who won the opening set 6-3.
However, Sandgren made a strong comeback, winning the second 6-2, followed by a similar dominance in the third.
As Federer looked to be struggling with Sandgren's backhand, he increased the rally in the fourth set to win the tie-breaker 10-8, before sealing the fifth in a commendable fashion.
The match turned out to be a good test of endurance for Federer as he would be taking on defending champion Novak Djokovic of Serbia in the semis.
Djokovic, who is the defending champion and the current world number two, would be the potential threat to Federer, as the former is eyeing his record eighth AO title and his 17th Slam.
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