Allan stars in Treviso win
Zebre had won both meetings between the sides last season, and looked good heading into half-time in front following Dries van Schalkwyk's try.
However, in the second half it was Treviso, sitting bottom of the Pro12 heading into the game, who started to shift the momentum their way to run out emphatic winners.
And having given his side the lead with a third penalty, Allan pounced for an opportunistic try which ensured there would be no comeback for Zebre, especially once Luca Sperandio ran in an intercept try to put the home team out of sight.
The visitors at least had the final say, with Kayle van Zyl going over in the final seconds, but it was too little too late.
Treviso made the better start with Robert Barbieri coming desperately close to scoring, only for Carlo Canna to get back and force the error as he reached for the line.
Still, they took the lead midway through the half when Mattia Bellini was penalised, allowing Allan to open the scoring with a penalty.
Zebre could have levelled matters following a line-out steal by George Biagi and then a scrum penalty by Edoardo Padovani's effort from 45 metres out fell short of the posts.
The visitors took the lead just after the half-hour. However, when Biagi chose to go to the corner from a penalty. Using their powerful pack, Zebre rumbled over, with Van Schalkwyk emerging from the pile of bodies. Carlo Canna's conversion made it 7-3 heading into the final minutes of the half.
Right on the stroke of half-time Treviso got back to within a point, Allan taking advantage of an offside to slot his second penalty of the evening.
That appeared to inspire the home side, and they were first to score in the second half, Allan again on target after Dario Chistolini had given away the penalty.
Leading 9-7, Treviso moved two scores clear thanks to their inspired flyhalf, with Allan grabbing his first try of the season on 55 minutes.
Taking advantage of a lost ball from Canna, Allan scooped up possession and raced over for the score. His conversion made it 16-7 for Treviso who looked to be in control.
Allan could have stretched the lead further with a penalty which fell just short, followed by a drop goal that was off-target, but the home team looked to be in total control heading into the final stages.
Zebre threw everything at their hosts in search of a try to cut the deficit, but instead it was wing Sperandio who picked off a Canna pass and sprinted in for Treviso's second try. Allan again converted and at 23-7 there was no way back.
Zebre did at least get a second try before time was up, with replacement Van Zyl going over on the left, but Canna could not convert from out wide on a difficult evening.
The scorers:
For Treviso:
Tries: Allan, Sperandio
Cons: Allan 2
Pens: Allan 3
For Zebre:
Tries: Van Schalkwyk, Van Zyl
Con: Canna
Teams:
Treviso: 15 Luke McLean, 14 Angelo Esposito, 13 Tommaso Benvenuti, 12 Alberto Sgarbi (captain), 11 Luca Sperandio, 10 Tommaso Allan, 9 Tito Tebaldi, 8 Marco Barbini, 7 Abraham Steyn, 6 Robert Barbieri, 5 Dean Budd, 4 Marco Fuser, 3 Simone Ferrari, 2 Davide Giazzon, 1 Alberto De Marchi.
Replacements: 16 Roberto Santamaria, 17 Matteo Zanusso, 18 Tiziano Pasquali, 19 Jeff Montauriol, 20 Marco Lazzaroni, 21 Giorgio Bronzini, 22 Ian McKinley, 23 Luca Morisi.
Zebre: 15 Edoardo Padovani, 14 Mattia Bellini, 13 Giulio Bisegni, 12 Tommaso Castello, 11 Giovanbattista Venditti, 10 Carlo Canna, 9 Marcello Violi, 8 Andries Van Schalkwyk, 7 Johan Meyer, 6 Derick Minnie, 5 George Biagi (captain), 4 Quintin Geldenhuys, 3 Dario Chistolini, 2 Tommaso D'Apice, 1 Andrea Lovotti.
Replacements: 16 Carlo Festuccia, 17 Bruno Postiglioni, 18 Pietro Ceccarelli, 19 Valerio Bernabò, 20 Federico Ruzza, 21 Guglielmo Palazzani, 22 Tommaso Boni, 23 Kayle Van Zyl.
Referee: Marius Mitrea (Italy)
Assistant referees: Emmanuele Tomò (Italy), Simone Boaretto (Italy)
TMO: Carlo Damasco (Italy)
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