Liverpool boss Rafa Benitez is being linked with AC Milan.
Leonardo took over from Carlo Ancelotti last summer and after some encouraging results before Christmas, Milan have struggled in recent weeks, including a 2-0 derby loss to Inter.
Milan face Manchester United in the Champions League next week which will see DavId Beckham take on his former club.
With city rivals Inter almost certain to retain their Serie A crown, there is growing pressure on Milan to win the Champions League.
The Italian giants have faced Benitez twice in the final of the competition with the Spaniard delivering the trophy to Anfield in 2005 before Milan gained their revenge two years later.
But as MIlan prepare for the visit of United, Benitez - also wanted by Juventus - and former Tottenham manager Juande Ramos, recently sacked by CSKA Moscow, have been touted as possible successors to Leonardo.