Hyeon Chung, left, became the first Korean tennis player — male or female — to reach a Grand Slam semifinal. (AP Photo/Dita Alangkara)

The much-anticipated matchup between Korean rising tennis star Hyeon Chung and 19-time Grand Slam champion Roger Federer at the Australian Open semifinals came to an anticlimactic and painful end on Friday. Chung, the first Korean — male or female — to reach a Grand Slam semifinal, was forced to retire with an injury that was later revealed to be severe blisters.

Down 6-1, 5-2, Chung gingerly walked over to the chair umpire and called it a day after 62 minutes of play, as some fans at Rod Laver Arena in Melbourne let out a groan of disappointment. Federer, the No. 2 seed, will vie for his 20th Grand Slam title against sixth-seeded Marin Cilic in Sunday’s final.

“I think I did right thing,” Chung said in his post-match news conference. “If I play bad thing on the court, it’s not good for the fans and audience as well. I’m happy to be able to make semis in Grand Slam. I want to be stronger next year.”

Hours later, Chung posted a photo of his beat-up right foot, further explaining his reason for retiring on the biggest stage of his young tennis career.

His agent, Stuart Duguid, told reporters after that match that Chung had “blister under blister under blister. He had it shaved off. Now it’s red raw. They tried injections to see if it numbed the pain. It didn’t work. Much worse than a regular blister.”

(Warning: the photo below features nasty blisters and may not be appropriate lunchtime viewing.)

“Tonight, I tried very hard to bring my utmost energy to the tennis court as usual,” Chung wrote on Instagram. “However, I had to make a tough decision given that I cannot compete 100% against Roger, in front of many tennis fans. Please understand. I wish all the best luck for @rogerfederer in the finals.”

With his charismatic personality and unique on-court glasses, the 21-year-old Chung has been the breakout star of this year’s Australian Open.

Ranked No. 58 in the world, Chung defeated multiple seeded players including No. 4 Alexander Zverev in the round of 32 and 14th-seeded Novak Djokovic in the round of 16, to reach the semifinal against Federer, arguably the best male player in the history of the sport.

After the match, Federer said he knew his opponent “was having issues with his feet” heading into the contest, but praised Chung’s future and how he handled himself in Melbourne.

“I think he’s going to have a lot of success,” Federer said. “At what stage, how much, we will see. I did see today why he beat the players like Novak, Sascha [Zverev], other players in the past. He’s very steady mentally. Today I’m sure he was having a lot of pain with his feet. Otherwise, why would you retire in such a big-match situation? And you couldn’t tell almost. I like that about the idea of hiding any problems from the opponent. That was very impressive, to be honest.”

Federer, 36, has yet to drop a set at this year’s Australian Open and has lost only once in nine matches to Cilic, whom he beat in straight sets at last year’s Wimbledon final.

But Cilic’s only victory came in a hard-court Grand Slam tournament, when he swept Federer in straight sets in the 2014 U.S. Open final on his way to his lone Grand Slam title.

Cilic, 29, scored a straightforward, 6-2, 7-6 (7-4), 6-2, win over 23-year-old Kyle Edmund of Great Britain on Thursday in the other semifinal.

“I just have to play a good match,” Federer said. “At this point it’s not about having to improve anything in particular. I think I’ve done everything pretty well, you know. I just hope I’m going to have a good start to the match. I hope I can mix up my game. I hope I can start serving well from the get-go, not get into too much trouble early. I hope I can read his serve and all these things.”

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