Kammala jumla mai zuwa: A lokacin da yake a kulob din, aikin Gattuso da iyawa a matsayin mai cin kwallo daga baya ya baiwa manajan Milan Carlo Ancelotti damar sanya dan wasan tsakiya Andrea Pirlo tare da shi a cikin wani yanayi mai kirkira, yayin da Gattuso ya goyi bayansa a cikin rawar da ya fi zurfi, a matsayin dan wasan tsakiya mai karewa; wannan haɗin gwiwar ta tsakiya ya kasance mai mahimmanci ga nasarar Milan ta gida da ta duniya a karkashin Ancelotti, wanda ya haɗa da Coppa Italia, UEFA Champions League da UEFA Super Cup a 2003, da kuma taken Serie A da kuma gasar cin kofin duniya ta UEFA a shekarar 2003.
Supercoppa Italiana a shekara ta 2004. Gattuso ya sanya hannu kan yarjejeniyar kwangila tare da Milan a watan Yunin 2003 kuma a watan Oktoba 2004. A wannan lokacin, Gattuso ya kuma kai wasan karshe na gasar zakarun Turai ta 2005 tare da Milan, amma Liverpool ta doke shi a bugun fanareti, bayan da ya fara jagorantar 3<unk>0 a hutun rabin lokaci.