The Viola won 2-0 via goals from Federico Chiesa and substitute Dusan Vlahovic.
“The lads did so well in their third game in a week, so we had to be organised, have the right attitude and the lads were exhausted by the end, but put in the performance they needed to bring home an important victory," Iachini told DAZN.
“They played with heart and we saw the fruits of our labour in these first couple of weeks working together. We're on the right track and hope to keep improving.
“We are doing better filling the box with more players going forward, although we need to finish the chances more accurately now that we're getting bodies in the penalty area.
“The lads are doing double training sessions and video work too, so we're making the right movements, even if sometimes we don't have the energy to get there in time. That will come, we've been together for 18-19 days and have real margin for improvement.
“We must improve in terms of intensity and stamina, but in the meantime, it was important to keep the team tight and ensure we didn't have to run too much for the positive transitions that way."