Gattuso's managerial career:
At Sion lasted from February 25th till May 13th (2013)
At Palermo lasted from August 19th till September 25th (2013)
At OFI Crete (Greece) lasted from June 5th till December 30th (2014, he resigned himself though, first time in October and second time in December)
At Pisa (Lega Pro, later Serie B) was head coach in 2015/16 and guided them to Serie B, after the season resigned and then signed again, next season finishing second last in Serie B, Pisa scoring mighty 23 goals in 42 games
Doesn't seem like the best available option for Milan, is he really the new head coach and not care-taker manager?