SV Werder Bremen won its first ever German double, clinching both Bundesliga and the DFB-Pokal, Werder lost both Aílton and defensive senior talisman Mladen Krstajić to Schalke 04, Krstajić is a former Serbian footballer who played as a centre back, born on which date?
2003–04 SV Werder Bremen season:  However, Werder lost both Aílton and defensive senior talisman Mladen Krstajić to Schalke 04, since both refused to sign new contracts with the club.
i don't know