Though Jeong only played the last 10 minutes, it provided a temporary distraction from speculation over Niko Kovac's future as coach following the defending Bundesliga champion's faltering start in the league.
Bayern is already nine points behind leader Borussia Dortmund after just 12 matches and hopes of a record-extending seventh consecutive title are fading. Former Arsenal manager Arsene Wenger has been touted as a possible successor for Kovac.
Jeong, who joined Bayern in January from Incheon United, was given his chance to shine because of a number of injuries. He showed a glimpse of his potential as Bayern earned its place in the last 16 of the Champions League.
"I'm very happy and incredibly proud to have played my first game for this big club," Jeong said. "It was a goose-bumps moment for me, an indescribable feeling that I'll never forget." Jeong, a speedy winger who likes to take on defenders and shoot at goal, was attracting attention with his performances for Bayern's reserve side in the fourth-tier regional league in Bavaria. He scored six goals and set up three more in 16 appearances.
Similar in style to France winger Franck Ribery, Jeong will likely get more chances to shine with the senior squad once Ribery and Arjen Robben finally retire, though he will also have to battle with Kingsley Coman - due to return soon from injury - as well Germany forward Serge Gnabry. Canadian youngster Alphonso Davies is due to join the team in January.
Jeong is eager to build on his short taste of the big time. "This incredible experience drives me on to keep working hard so I can take the next steps and more appearances follow," said Jeong, who has German lessons most days to help his integration in Munich.
Jeong was relatively old at 10 when he started playing soccer. One year ago, he was playing in front of as little as 10 spectators. "I really wanted to go to Europe," Jeong told Kicker magazine before his appearance against Benfica. "If you want to develop, you have to do that. Everyone in South Korea who can play well is no longer there."
Jeong's agent arranged trials at Cologne, Augsburg and Salzburg. But Bayern snapped him up and gave him a contract through June 2022. "His dynamism, speed, technical ability and intelligence were obvious," said Jochen Sauer, the director of Bayern's youth program. "When we take a player from so far away, then we think that there's still potential for development. We owe it to the boy and his parents that we don't just sign him to make up numbers in the team."
While his heroes are Neymar and Son Heung-min, Jeong has the possibility of learning directly from Ribery and Robben. "They're fully focused in each training session and want to score goals right to the end," Jeong said. "I can learn a lot from their technique and how they move."
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