But they fell short in the end of preventing victory for Les Kiss' fifth-placed visitors, who wrapped things up by crossing for a fifth and sixth time in the final 10 minutes as their top-four push continues.

Ulster are now five points behind fourth-placed Scarlets with a game in hand.

They looked set for a simple afternoon's work when they raced ahead via tries in the sixth minute from Chris Henry and 13th from Ruan Pienaar, who converted on both occasions.

But having gone 14-0 up inside the opening quarter of an hour, the Irish side then appeared guilty of complacency as Guglielmo Palazzani notched a try, conversion and penalty to see Zebre go in at the break only four points behind.

There was a similar pattern after the break, with Stuart Olding and Jacob Stockdale registering Ulster tries within the first 10 minutes and Pienaar adding the extras before the home team hit back through Mattia Bellini's try, converted by Palazzani, to make it 28-17.

Kiss' men, with Ireland centre Jared Payne brought on for his return from a kidney problem, then pulled away again in the closing stages thanks to Robbie Diack and David Busby, Pienaar converting the first of those efforts but not the second.