Simon Mason scored seven penalties

Their former European Cup hero Mason was on target with two early penalties to give the home side a six-point advantage.

Ward got the first touchdown in the 25th minute after a sustained push by the visitors and David Humphreys landed a fine conversion to put Ulster into a 7-6 lead.

Two minutes later Ulster got a second try, scored by Topping.

It stemmed from Gary Longwell's take at a line-out. Doak and Humphreys moved the ball out to Jonathan Bell.

Bell charged through one tackle and then fed winger Topping whose try was converted by Humphreys.

David Humphreys scored 23 points in Italy

Mason cut the deficit with two more penalties in the 33rd and 38th minutes.

Humphreys landed a stoppage time penalty for Ulster but there was still time for Mason to land two more penalties for Treviso to give them an 18-17 interval lead.

Humphreys edged Ulster into the lead again with a penalty early in the second half before consolidating Ulster's position further with a 57th minute try.

It was made by the pack with scrum-half Doak passing the ball out to Humphreys who touched down before adding the conversion which made it 27-18 for Ulster.

Mason made it seven penalties from seven attempts on the hour mark.

Clinch victory

Humphreys landed another penalty in the 67th minute.

But the Italian club came back yet again and scored their first try through winger Massimiliano Perziano.

Mason converted to close the score to 28-30 with 10 minutes remaining.

Humphreys landed a stoppage time penalty to clinch Ulster's vital victory.

Benetton Treviso: S Mason; M Perziano, W Pozzebon, S Magorian (Preo 62min), N Mazzucato; F Mazzariol, P Richards; P Ribbens, A Moscardi (capt), F Porperzi, W Visser (Ungaro 79min), A Grippi (Campbell 58min), C Checchinato, D Edwards, M Bergamasco.

Ulster: P Wallace; J Popping, S Stewart (Constable 53min), J Bell, T Howe; D Humphreys, N Doak (Campbell 62min); J Fitzpatrick, P Shields (Crick 71min), S Best (Boyd 69min), J Davidson, G Longwell (Blair 69min), T McWhirter (McMillan 62min), R Nelson, A Ward (capt).

Referee: P Adams (Wales).