Inter Milan coach Walter Mazzarri insists there shouldn't be any concern over preseason results for Serie A clubs.

Mazzarri's Inter were defeated 4-0 by Valencia in America, while Juventus lost 3-1 to LA Galaxy and Porto beat Napoli 3-1 over the weekend.

"The losses probably occurred because we Coaches from the Italian League know what kind of preparation it requires," Mazzarri told Inter Channel.

"Our preparation is all based on work for the League and the work will pay off…

"In Italy we're forced to work in this way," he added. "You have to choose whether you want to come off looking good in these important friendlies or if you want to work very little."