Grand Slam tennis can be a major stress test taxing even the calmest players.
Incensed by the chair umpire's call in the decisive tie break, Pablo Carreno Busta went ballistic losing his cool and ultimately the match.
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Marathon man Kei Nishikori battled back from a two-set hole out-dueling Carreno Busta, 6-7 (8), 4-6, 7-6 (4), 6-4, 7-6 (8), in an exhilarating five hour, five-minute thriller to reach the Australian Open quarterfinals for the fourth time.
At the end of a painful loss, the Spaniard walked around the net to shake Nishikori's hand before erupting in a primal scream of frustration and hurling his red Wilson racquet bag across the court.
Carreno Busta held an 8-5 tie break lead when a controversial call turned the match.
The Spaniard's shot hit the top of the net and skimmed over, Nishikori was waiting where he knocked off an easy winner, but the linesman incorrectly ruled Carreno Busta's net-cord out.
The 23rd-seeded Spaniard argued he stopped play after the incorrect call therefore the point should be replayed.
Rather than replaying the point, chair umpire Thomas Sweeney ruled the incorrect out-call did not impact the point since Nishikori was in position to finish the easy sitter and put the shot away.
The eighth-seeded Japanese did not lose another point in scoring his second fifth-set tie break win of the tournament.
After a brutal loss, Carreno Busta entered the interview room and apologized for his outburst admitting he lost it.
"Obviously I'm very sad, no, because after five hours fighting, after five hours' match, the way that I leave from the court wasn't correct, and I'm so sorry, because that's not mine," Carreno Busta said. "But I think that the referee missed, the umpire who is near the court missed, and, well, I try to leave faster as possible when I lost that last point, because I know that in any moment I lost the head.
"But it's tough, no, to me to leave Australian Open like this, because I think that I played really good. I play an unbelievable match. Also Kei, he play really good, and that's sad to leave like this."
Nishikori advanced to his fourth Australian Open quarterfinal where he will play world No. 1 Novak Djokovic.
The ninth-seeded Japanese said his comeback from two-sets down overshadowed the controversial point.
"Well, that was important point, too, but, I mean, you should ask how I came back from two sets down," Nishikori said. "That was only one point.
"I mean, maybe affect him, but, you know, he took some time and maybe it could affect me. I mean, I'm really glad how I came back. Yeah, I don't even know how I come back but very happy to win today."
Photo credit: Mark Peterson/Corleve