Singer, songwriter and member of the South Korean boy band BTS Jin (Kim Seok-jin) was among the spectators watching Casper Ruud face Nicolas Jarry in the second round of the Korea Open on Thursday.Ruud was in action on Center Court in his Round of 16 clash against Jarry, who gave the Norwegian a tough fight before going down 6-2, 3-6, 6-3. A video of Jin at the Seoul Olympic Park Tennis Center subsequently went viral on social media, and many fans were quite excited to see him.ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen2680611166Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUETennis Twitter was also understandably excited at spotting the Bangtan Boys star. One fan stated that Jin's presence did more for the promotion of tennis than the ATP."He did more for the promotion of tennis than the atp did by just showing up to a match lmao look at the likes," a tweet read.anna 🎾 inactive era@rafasfedererhe did more for the promotion of tennis than the atp did by just showing up to a match lmao look at the likes twitter.com/BRILLER__613/s…브리이에@BRILLER__613석지니 테니스경기 보러 갔구나 315석지니 테니스경기 보러 갔구나 ‼️ https://t.co/66yRyhvhTHhe did more for the promotion of tennis than the atp did by just showing up to a match lmao look at the likes 😭 twitter.com/BRILLER__613/s…"Casper and his ongoing connection with random celebrities is so funny to me," another fan wrote.Jerry@GoffwanskaCasper and his ongoing connection with random celebrities is so funny to me twitter.com/atptour/status…ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen82Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUECasper and his ongoing connection with random celebrities is so funny to me😭😭😭 twitter.com/atptour/status…"started his day with the LOUD reminder on his main and now he’s out being popular guy in the audience who steals everyone’s thunder KING TIER kim seokjin," one user wrote.july⁷//🃏☔️🏝@riseofducktanstarted his day with the LOUD reminder on his main and now he’s out being popular guy in the audience who steals everyone’s thunder KING TIER kim seokjin twitter.com/atptour/status…ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen42Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUEstarted his day with the LOUD reminder on his main and now he’s out being popular guy in the audience who steals everyone’s thunder KING TIER kim seokjin twitter.com/atptour/status…"BTS Jin’s presence which cannot be hidden even if he’s wearing a hat and a mask," one fan tweeted.ARHIVABTS⁷@ArhivaBTS220929 #JIN 🗣 BTS Jin’s presence which cannot be hidden even if he’s wearing a hat and a mask twitter.com/atptour/status…ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen41Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUE220929 #JIN 🗣 BTS Jin’s presence which cannot be hidden even if he’s wearing a hat and a mask twitter.com/atptour/status…"He is having a staring competition with the camera," another fan wrote.jjwanswifey👩🏿‍🦰🃏@yourssomaHe is having a staring competition with the camera twitter.com/tennistv/statu…Tennis TV@TennisTVThe stars are out in force #KoreaOpen @CasperRuud98 @BTS_twt169257517The stars are out in force 🌟#KoreaOpen @CasperRuud98 @BTS_twt https://t.co/d4HI7DEIn8He is having a staring competition with the camera 💀 twitter.com/tennistv/statu…Here are some more fan reactions to the BTS star's presence at the Korea Open:Ena⁷@sylverlines7okay, adding this to the list, to have a higher chance of seeing @BTS_twt in person:1. go to other artists' concert2. watch basketball game3. watch tennis match twitter.com/TennisTV/statu…Tennis TV@TennisTVThe stars are out in force #KoreaOpen @CasperRuud98 @BTS_twt38853The stars are out in force 🌟#KoreaOpen @CasperRuud98 @BTS_twt https://t.co/d4HI7DEIn8okay, adding this to the list, to have a higher chance of seeing @BTS_twt in person:1. go to other artists' concert2. watch basketball game3. watch tennis match 🆕 twitter.com/TennisTV/statu…JN@jennieriseshim going to a tennis game right after calling that person out for going to court is so funny twitter.com/atptour/status…ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen117156Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUEhim going to a tennis game right after calling that person out for going to court is so funny💀 twitter.com/atptour/status…bora 💜 (slow)@modooborahae🗣 BTS Jin who is showing his presence/aura cannot be hidden even while wearing a mask and a hatJin went to go see a Korea Open tennis match! @BTS_twt #BTS #방탄소년단 #JIN 1720483🗣 BTS Jin who is showing his presence/aura cannot be hidden even while wearing a mask and a hatJin went to go see a Korea Open tennis match! @BTS_twt #BTS #방탄소년단 #JIN https://t.co/7y8pHqGxOUseokjin_rocks 🐟 Mapler@Kahoko271@atptour @BTS_twt @CasperRuud98 Seokjin has been very passionate about tennis. @atptour let's have a friendly match with #BTSJIN ?? It will a wonderful match i bet 114@atptour @BTS_twt @CasperRuud98 Seokjin has been very passionate about tennis. @atptour let's have a friendly match with #BTSJIN ?? It will a wonderful match i bet ☺️anita⁷ •ᴗ•🐰🏁eenie, meenie, miney, moe@tabodanita@atptour @BTS_twt @CasperRuud98 Look at him so effortless handsome30@atptour @BTS_twt @CasperRuud98 Look at him so effortless handsomeSumu⁷/ Moonie Day🍀🐨@Giggly_Koo@atptour @BTS_twt @CasperRuud98 that nervous glance & pupil shaking as if he ain't the member of THE biggest boyband in the world. @atptour @BTS_twt @CasperRuud98 that nervous glance & pupil shaking as if he ain't the member of THE biggest boyband in the world. 😭Vicky@MsConJiniality7AND NOW JIN IS WATCHING TENNIS?!? I swear, if JK pops up at a boxing meet it’s all over for me. twitter.com/atptour/status…ATP Tour@atptourCasper got a new fan Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen217287Casper got a new fan 👀👋 Jin! @BTS_twt | @CasperRuud98 | #KoreaOpen https://t.co/acm6FzxqUEAND NOW JIN IS WATCHING TENNIS?!? I swear, if JK pops up at a boxing meet it’s all over for me. twitter.com/atptour/status…Casper Ruud to face Yoshihito Nishioka in Korea Open quarterfinalsCasper Ruud entered the quarterfinals of the Korea OpenCasper Ruud booked his place in the quarterfinals of the Korea Open by defeating Nicolas Jarry 6-2, 3-6, 6-3. The Norwegian, who received a bye in the first round, started the match strong and got two breaks to take a 4-0 lead in the opening set, which he eventually won 6-2. But Jarry fought back in the second set and broke Ruud in the fourth game to take a 3-1 lead. The break turned out to be decisive as the Chilean won the set 6-3 to force the match into a decider.The final set saw both players dominating their service games until the World No. 2 made the decisive break in the sixth game. Jarry then fought hard and saved three match points but the 23-year-old won the final set 6-3 to book his place in the quarterfinals.Ruud will next take on Japan's Yoshihito Nishioka, who beat compatriot Taro Daniel 6-2, 6-4. This will be the second career meeting between the pair, following their second round clash in last year's Madrid Open which Ruud won 6-1, 6-2.The winner of the match will face either Mackenzie McDonald or Aleksandar Kovacevic in the semifinals of the Korea Open.