Fans jeered and threw objects after yesterday afternoon's 2-0 result for the minnows.
"It's an ugly defeat," confessed the Coach. "Now we mustn't lose faith in the work we are doing, as in the first half we created so many chances and were simply unable to find the goal.
"A defeat like this must not affect our work. In the second half, a scorching counter-attack from Siena hit us hard.
"This is the moment to stick together. I have great faith in the lads and we mustn't back up even an inch.
"Today Inter created more scoring opportunities than Siena, but we do tend to struggle a little in the middle when our opponents go on the counter, as our full-backs tend to attack.
"Up until Simone Vergassola's goal, Siena were only dangerous from corners. We are a new squad and it takes time to create the right balance."