Cardiff Blues marked Jonah Lomu's home debut with a crucial bonus-point Heineken Cup win in front of a near packed house at the Arms Park.
Blues (22) 43
Tries: Rush (2), R Williams (2), Quinnell, Sowden-Taylor
Cons: N Robinson (5)
Pen: N Robinson
Calvisano (8) 16
Tries: Van Schalkwyk, Zaffiri
Pens: Kruger (2)
The wing could not get on the score board, though, a first-half brace for another ex-All Black - man-of-the-match Xavier Rush - setting them on the way.
Rhys Williams got two, his 59th-minute try easing nerves. Craig Quinnell and Robin Sowden-Taylor also scored.
Calvisano's tries came from Jacobus van Schalkwyk and Maurizio Zaffiri.
The Blues had installed 2,000 extra seats to cater for Lomu-mania, but it was the visitors who opened the scoring with a Herkules Kruger penalty.
Lomu started the move that led to the first try, though, the giant wing cutting in-field where his forwards won quick ruck ball.
Excellent handling by Nicky and Jamie Robinson saw the ball reach Rush on the left wing, the number eight crossing for the try.
Nicky Robinson converted, and added a penalty after good build-up work from the impressive centre partnership of Marc Stcherbina and Jamie Robinson.
With two Calvisano defenders watching Lomu, Rhys Williams dummied and straightened to cross for the second try.
Nicky Robinson then made a great midfield break and found the supporting Rush, whose fantastic pick-up gave him his brace.
The Italians hit back before half-time when Massimo Ravazzolo took advantage of hesitant defending to put van Schalkwyk in at the corner.
Kruger added his second penalty after the break as the visitors frustrated the Blues' search for a fourth-try bonus point.
But with 20 minutes to go, Mike Phillips broke from a tap penalty and linked with Rush.
He carried well before feeding Craig Morgan, who drew the defence and put Rhys Williams in at the corner.
Calvisano flanker Warren Brosnihan was sin-binned for killing the ball, and their 14-man pack was barrelled backwards from a scrum under the posts for Quinnell to crash over.
The game seemed in danger of fizzling out until a huge fight four minutes into stoppage time led to sin binnings for Martyn Williams and Matteo Pratichetti.
A fired-up Calvisano drove a short-range line-out well for a consolation try for captain Zaffiri.
As the game entered its 90th minute, visiting lock Justin Purll was sin-binned, and from the resultant penalty Sowden-Taylor crossed for the Blues' sixth and final try.
Cardiff Blues wing Jonah Lomu:
"I feel as though I am going in the right direction.
"Sometimes, the ball goes your way and sometimes it doesn't. I have got to make sure I do what is best for the team.
"I am confident in what I've got. I am growing each week, although today wasn't my day to open up.
"I didn't feel any added pressure because of the crowd today. It should be uplifting when you have that sort of support."
Cardiff Blues coach Dai Young:
"There were a lot of cheap shots and there was a lot of gouging.
"We expected a lot of niggle. We had it last week in Calvisano, and we had it this week. I thought the players stood up for each other.
"We expected it, but you don't have to like it. It is disappointing, but you have got to put up with it, and we were concentrated on trying to keep everyone on the field."
Cardiff Blues: R. Williams, Morgan, J. Robinson, Stcherbina, Lomu, N. Robinson, Phillips, Jenkins, R. Thomas, M. Jones, D. Jones, Sidoli, A. Powell, M. Williams, Rush.
Replacements: Davies for Stcherbina (69), L. Thomas for N. Robinson (71), R. Powell for Phillips (71), B. Evans for M. Jones (54), Sowden-Taylor for A. Powell (76). Not Used: Goodfield, Quinnell.
Calvisano: Vian-Schalkwyk, Nitoglia, Pratichetti, Kruger, Tuta-Vodo, Patelli, Griffen, Perugini, Intoppa, M. Castrogiovanni, Mandelli, Purll, Brosnihan, Zaffri, Zanni.
Replacements: Ravazzolo for Nitoglia (29), Bocca for Perugini (78), Ghiraldini for Intoppa (64), Cittadini for M. Castrogiovanni (76), Cattina for Zaffri (80), Candiago for Zanni (80). Not Used: Cagnoni.
Referee: Christophe Berdos (France)