Ulster defence coach Jonny Bell admitted his side had to dig deep in the Italian heat to overhaul Aironi in their 25-19 victory.
In sweltering conditions, tries from Dan Tuohy, Ian Whitten and Craig Gilroy proved decisive for Ulster who have won both their opening matches.
The performance however was littered with mistakes and although some may be disappointed by the failure to pick up a bonus point, Bell says it was understandable given how hard they were pushed.
He said: “We are delighted to come away with the win, but we’re a little bit disappointed not to capitalise on the opportunities that we had to get the bonus point at the end.
“It’s obviously very draining playing in that kind of heat and with the attritional nature of the Aironi team, the contact point is going to crucial.
"Today, that battle at the gain line was energy sapping.
“Some decisions were made at certain stages that put us under a bit of pressure but fair play to the boys, they worked very, very hard today in difficult conditions and we got that win.”