The pair have only just returned to action after career-threatening conditions and the Rossoneri director has admitted that they have been sorely missed by the team
In his first start since recovering from the effects of an emergency heart procedure last November, Cassano scored one goal and created two others, while Gattuso, making his third Serie A appearance since overcoming career-threatening ocular problems, was his usual dynamic self in the Rossoneri midfield.
Galliani was enthused by the pair's performances and insinuated that AC Milan would not be currently sitting three points behind league leaders Juventus had both players been available for selection.
"The real regret for this year, as I said it to [Silvio] Berlusconi on the phone, is about Gattuso and Cassano," the Rossoneri official is quoted as saying by his club's official website.
"With the two of them we would have gained some more points, the team has had more injuries than normal."
Galliani, though, is relieved to finally have both men back and admitted that he was particularly touched by Cassano's celebration when he scored against Siena.
The attacker rushed to embrace Dr. Rodolfo Tavano, who treated the forward after the stroke he suffered while returning home from last October's clash with Roma.
"Dr. Tavana was fundamental to Antonio and he knows what he has done for him that night. Their embrace was beautiful and meaningful."
Despite AC Milan's victory over Siena, Juve can clinch the title if they win their next two games, against Lecce and Cagliari.