Question: Who was the football star born in 1974 that left Bayer Leverkusen to join another club, after the club did not win the Champions League and domestic league in 2001-02?
Sentence (from "2001–02 Bayer 04 Leverkusen season"): Bayer Leverkusen became the second club to finish runner-up in both the Champions League and domestic league and cup competitions in the same season after Barcelona in 1986, with a potential treble unravelling in the final couple of weeks of the season, resulting in no trophies won at all, plus the defections of stars Michael Ballack and Zé Roberto to Bayern Munich.
Relevant evidence: Yes