Casellato's men have been a force to be reckoned with at home so far, backing up wins over Cardiff Blues and rivals Zebre with a draw against GUINNESS PRO12 champions Leinster, as well as running several other sides close.
But away from home their only victory has been a 26-16 triumph at Zebre, and Sunday's 53-5 humbling at Connacht was characteristic of Treviso's results this season off Italian soil.
And while Casellato is baffled by the discrepancy, with three home games on the horizon the former Azzurri scrum-half is hoping his men can climb further off the foot of the GUINNESS PRO12 table.
"We are asking ourselves the question of why abroad - apart from our matches against Cardiff Blues and Glasgow Warriors - it always ends the same way," he told La Tribuna di Treviso.
"Once again there are so many aspects to analyze. In Galway we wanted to play against the wind for the first half, trying to limit the damage and then turn the wind in our favour in the second.
"Unfortunately it went wrong, and then we collapsed in the second half and lost our heads a bit.
"Another problem is that many players are not used to these trips. Connacht only beat us 9-6 at the Stadio Monigo, and on Sunday we were missing a lot of our international players who are used to the travel.
"Now we need to erase the negatives and look at the positive aspects. I would say that some of the guys responded in the second-half, and games like that are also important for the feedback and learning lessons.
"Let us now focus on the next three home games: Edinburgh, Ospreys and Newport Gwent Dragons. Edinburgh is a very physical team, and that will be a tough test in particular."
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