Byrne's hat-trick puts Leinster back on top
The 22-year-old put his side ahead late in the first half after Zebre made a fast start, before two in the second period wrapped up a comfortable victory – preserving Leinster’s 100 percent winning record against their hosts.
Centre Tom Daly scored on his Leinster debut after Andries van Schalkwyk put Zebre ahead before Byrne took over in the second half.
Jack Conan also scored for the visitors, who have won seven of their eight league games so far this season.
Leinster Director of Rugby Leo Cullen made seven changes following their 24-13 victory against Connacht last weekend, with Daly the headline selection.
Prop Andrew Porter made his first start for the club, while hooker Richardt Strauss made his first appearance of the season.
Zebre were on top as they won the early aerial battle, but handling errors cost them an almost certain try as they coughed up the ball at the Leinster five-metre line.
But when Mike McCarthy was yellow carded, as Leinster were penalised for persistent fouling, they took the lead through Van Schalkwyk, who powered over for the game’s first try.
However, Leinster responded quickly as Daly scored following strong carries from Sean O’Brien and Conan, before Carlo Canna regained Zebre the lead with a penalty.
As the first half progressed, Leinster became more comfortable in possession and it was not long before they moved ahead for the first time courtesy of Byrne after a strong Barry Daly run.
Cullen made three changes in the pack after the break and the extra power immediately paid off after some ferocious work by the forwards created space outside, and Byrne scored his second try from Jamison Gibson-Park’s pass.
Isa Nacewa converted the score from wide on the right, giving Leinster a nine-point lead that they looked unlikely to lose after Canna missed a penalty minutes later.
Shortly after, Conan added the all-important fourth try to confirm a bonus point after Byrne, Noel Reid, Tom Daly and Gibson-Park combined to release the forward to score.
And Byrne wrapped up his hat-trick in style as flyhalf Ross Byrne found the wing to dot down after he climbed over fullback Edoardo Padovani to score.
Zebre pushed hard in the final ten minutes to get some points back, but some resolute Leinster defending kept the hosts at bay.
The scorers
For Zebre:
Try: Van Schalkwyk
Con: Canna
Pen: Canna
For Leinster:
Tries: Tom Daly, Conan, Byrne 3
Cons: Nacewa 4
Yellow Card: Mike McCarthy (Leinster)
The teams:
Zebre Rugby: 15 Edoardo Padovani, 14 Giulio Bisegni, 13 Matteo Pratichetti, 12 Tommaso Castello, 11 Giovanbattista Venditti, 10 Charles Reed, 9 Marcello Violi, 8 Andries Van Schalkwyk, 7 Johan Meyer, 6 Maxime Mbanda, 5 George Biagi, 4 Quintin Geldenhuys, 3 Dario Chistolini, 2 Tommaso D'Apice, 1 Andrea Lovotti
Replacements: 16 Carlo Festuccia, 17 Bruno Postiglioni, 18 Pietro Ceccarelli, 19 Federico Ruzza, 20 Derick Minnie, 21 William Palazzani, 22 Carlo Engelbrecht, 23 Simone Toys
Leinster Rugby: 15 Isa Nacewa, 14 Adam Byrne, 13 Tom Daly, 12 Noel Reid, 11 Barry Daly, 10 Ross Byrne, 9 Jamison Gibson-Park, 8 Jack Conan, 7 Sean O'Brien, 6 Dan Leavy, 5 Hayden Triggs, 4 Mike McCarthy, 3 Michael Bent, 2 Richardt Strauss, 1 Andrew Porter
Replacements: 16 James Tracy, 17 Peter Dooley, 18 Mike Ross, 19 Mick Kearney, 20 Rhys Ruddock, 21 Nick McCarthy, 22 Dominic Ryan, 23 Hugo Keenan
Referee: Nigel Owens (WRU)
Assistant Referees: Simon Rees (WRU), Filippo Bertelli (FIR)
Source: @PRO12rugby