Cup, Cha attracted the attention of an Eintracht Frankfurt coach Dieter Schulte, who had received an invitation to serve as an scout/observer at that tournament. In November 1978, Schulte sent a letter to the KFA (Korea Football Association), suggesting Cha's tryout in West Germany, who would be discharged from the ROK Air Force in January 1979. Cha had taken time off to leave for Frankfurt after the 1978 Asian Games in December and succeeded to contract with another Bundesliga club Darmstadt 98 by signing a six-month deal. However, he spent just less than a month in Darmstadt. The ROK Air Force didn't follow the contract with Cha, and ordered his return. After his debut match against VfL Bochum on 30 December, Cha returned to South Korea due to his complicated issue about military service on 5 January. He eventually spent the remainder of the duration of his military service until 31 May, and so could not play for Darmstadt. Eintracht Frankfurt After being discharged from the military service completely, Cha still wanted to play in Bundesliga, and joined Eintracht Frankfurt at age 26 in July 1979. He scored in three consecutive games from third to fifth matchday of the Bundesliga, making an immediate impact early in his new club. After the first half of his first season in Germany, he was classified as world class in the of kicker, a notable German football magazine. He was also acclaimed by showing great performances helping Frankfurt to win its first-ever UEFA Cup title. He was evaluated as the "unstoppable player" by Sir Alex Ferguson, (Aberdeen's manager at the time) and "one of the best attackers in the world" by Lothar Matthäus. (an opponent player at the UEFA Cup Final and the Bundesliga) In addition to a UEFA Cup title, he was named along with Karl-Heinz Rummenigge and Kevin Keegan in the Bundesliga Team of the Season by kicker. On 23 August 1980, Cha's spine had been cracked by Jürgen Gelsdorf, who had tackled behind him, but came back to the stadium after a month. Afterwards, he scored six goals in six matches of the 1980–81 DFB-Pokal, leading Frankfurt to the title. He became Frankfurt's top goalscorer for three consecutive seasons. Bayer Leverkusen However, Cha transferred to Bayer Leverkusen due to a financial difficulty of Frankfurt in 1983. In the 1985–86 Bundesliga, he scored his most goals in a single Bundesliga season with