The defending European Rugby Challenge Cup champions did end up 23-10 winners but they failed to add any points in the second half to let a potential bonus point slip from their grasp.
 
No club has ever won back-to-back titles in this tournament and while that is the ground-breaking target for Gloucester they will be far from satisfied with their second half display.
 
Nevertheless it was a 10th successive tournament win for the Cherry and Whites who will travel to La Rochelle in Round 2 hoping to make it 11 from 11.
 
Zebre – with just two wins from their previous 18 contests over three seasons in Europe, home and away against Brive last year – made early headway with forward drives from the line-outs but with less than eight minutes gone a flowing attack produced a fine corner try for wing Henry Purdy.
 
Outside half Billy Burns and flanker Ross Moriarty were prominent in the build-up to have the home faithful cheering on their feet and then when TMO Dermot Moloney was called into action by Irish referee Andrew Brace he ruled that Moriarty had just made the whitewash with two defenders unable to deny the Welsh international.
 
Heineken Man-of-the-Match Burns added an excellent conversion to make it a whirlwind point-a-minute start from David Humphreys’ men, the 21-year then on target with a couple of simple penalty goals to keep the scoreboard ticking over.
 
Things had certainly died down on the try front as the greasy conditions certainly made things more difficult.
 
But the wait for try No 3 was worth every second of the wait, an early candidate for try of the round coming courtesy of some sweet off-loading and support play with Callum Braley, Lewis Ludlow and Mark Atkinson heavily involved.
 
It was left to strong-running right wing Stevie McColl to provide the finishing touches from a fair way out to put them 23 points clear at the break.
 
The try bonus point was the next target for livewire skipper Jacob Rowan and his team-mates but the Italians started the half the stronger – Ludlow sent to kick his heels in the sine bin for 10 minutes after a general flare-up.
 
And his absence saw Zebre punish Gloucester with 10 points to warn the home side they were far from home and dry.
 
The depleted Gloucester pack were sent into rapid retreat at a close range scrum and referee Brace had no hesitation in awarding a penalty try to open the Italians’ account.
 
Outside half Edoardo Padovani added the conversion and penalty before Gloucester were restored to full strength but with the Zebre pack ruling the scrums at this stage as it was a real contest going into the final quarter.
 
New recruit and former All Black Jeremy Thrush marked his club debut with a solid performance before departing with 15 minutes to go and try-scorer Moriarty was back in defence to deny Zebre a second five-pointer.
 
The home eight also rose to the challenge at another attacking Italian scrum to prompt much back slapping but the elusive fourth try eluded them to leave them chasing that 11th straight win over in France on Thursday night.