Joe Schmidt’s men didn’t have it all their own way in Reggio Emilia but showed enough class to secure the four-try bonus point, thus taking them back into second position ahead of Glasgow.
Leinster scored five tries, one apiece for Tom Denton, Fergus McFadden, Fionn Carr, Dominic Ryan and Isa Nacewa.
Schmidt was a little annoyed they hadn’t managed to add a few more and stressed the need for improvement ahead of Saturday’s shootout against the Basque giants.
“It was a case of coming over, getting the points, and not picking up any injuries,” said Schmidt of their mission statement.
“We were good at times, sloppy at other times, and will definitely need to step it up a level next week.
“I felt we created two or three other chances we should have taken, and that we were quite wasteful overall.”
“It’s just as well that Johnny Sexton kicked seven out of seven.”
The reference to Sexton was notable. On his return to action following seven weeks on the sidelines, the Lions hopeful got 65 minutes under his belt, and proved an inspirational force for Leinster.
As to whether it will be enough to displace in-form deputy Ian Madigan ahead of the Biarritz clash remains to be seen.
Schmidt hinted the six-day turnaround may influence his selection, presumably in favour of Madigan.
But his appraisal of Sexton’s performance suggested he is still unsure.
“We would always back Johnny to make his kicks, but on top of that he got through a power of work,” said Schmidt. “He is a great general out on the field, and he gave us a fair bit of direction.
“In terms of next week, the six day turnaround would probably favour fresher players, but at the same time Jonathan is a marquee player for us.”
Sexton was at the heart of everything for a Leinster side which after 15 minutes looked as though they were on course for their biggest win of the season.
Patient, controlled build-up play was rewarded with two tries inside the opening quarter.
The first, a simple run-in for Denton out wide after some neat footwork and good hands by Andrew Goodman.
Shortly after, McFadden was skirting home from roughly the same position after Sexton’s killer pass saw him away.
The outhalf kicked both conversions as well as an earlier penalty, and one wondered whether the bonus point would come before half-time.
However, the momentum began to drop a little as the half wore on, and some desperately soft tackling saw Zebre tie up the scores before half-time, Sinoti Sinoti and Daniel Halangahu both crossing for converted tries.
Whatever Joe Schmidt said at the break seemed to have the desired effect and Leinster reopened a ten-point lead within five minutes of the second half.
Sexton firstly slotted home a penalty before angling a crossfield kick which stood up nicely for Nacewa, who in turn fed Carr for try number three.
Ryan added the all-important fourth after a sublime inside feed from Rhys Ruddock, before Nacewa put the icing on the cake with a fifth.
Carlo Festuccia snuck home for a late Zebre try but it proved little more than a consolation for the Italians.
Scorers for Zebre: Tries: Sinoti, Halangahu, Festuccia Cons: Halangahu 2 Pen: Halangahu.
Scorers for Leinster: Tries: Denton, McFadden, Carr, Ryan, Nacewa Cons: Sexton 5 Pens: Sexton 2.
ZEBRE: A Benettin (D Odiete 49-54); R Trevisan (D Odiete 54), G Venditti, M Pratichetti (L Orquera 65), S Sinoti; D Halangahu, A Chillon (T Tebaldi 48); M Aguero (A de Marchi 55), A Manici (C Festuccia 43); L Leibson (S Perugini 55); M Van Vuren (E Caffini 41), M Bortolami (capt); F Ferrarini (F Cristiano 64), M Bergamasco (A Manici 78), J Sole.
LEINSTER: I Nacewa; F McFadden, B O’Driscoll, A Goodman (A Conway 70), F Carr; J Sexton (C Marsh 65), J Cooney (I Boss 55); J McGrath (J O’Connell 65), R Strauss (A Dundon 62), M Bent (J Hagan 41); T Denton (Q Roux 64), D Toner; K McLaughlin, D Ryan, R Ruddock (S Jennings 64).
Referee: Neil Paterson (SRU).