Leali'ifano also kicked a second-half penalty while John Cooney kicked two penalties and a conversion in the opening 40 minutes.

Injury-hit Ulster failed to take adequate advantage of a yellow card shown to Benetton winger Andrea Bronzini late in the first half and struggled from there.

Benetton scored one try from Robert Barbieri while man of the match Tommaso Allan kicked four penalties and a conversion while sub Marty Banks added one second half penalty.

The kick-off was delayed as the Benetton team bus was involved in a minor accident, but the Italians were first to score when Allan kicked an early penalty.

He slotted a second nine minutes later before Ulster struck off a lineout maul when Cooney found Bowe on the right and the winger rounded the defence to score.

Cooney's well-struck conversion put Ulster ahead by a point at 7-6. That became 10-6 four minutes later when Cooney hit a long-range penalty.

The Ulster scrum-half missed with his next effort, though, after the Benetton scrum was penalised but Cooney made no mistake on the half hour from close-in after Bronzini was yellow-carded for a high hit on Louis Ludik.

Allan then missed a 34th-minute penalty but made amends four minutes later when Nick Timoney was penalised at a ruck and the half ended with Ulster leading 13-9.

After a fitful opening to the second half, Allan put the Italians one point behind with a 50th-minute penalty before a mix-up from a Paul Marshall box kick - on his 200th game - saw new cap Schalk van der Merwe pass straight to Barbieri who gratefully accepted the score.

Allan converted the 56th-minute try and Ulster now trailed 19-13. They responded and, after turning down a kickable penalty, Leali'ifano nailed a 63rd-minute penalty from long range.

Banks slotted a 73rd-minute penalty to push the Italians into a 22-16 lead.

With time running out, Ulster came again with Trimble surging over and Leali'ifano adding the critical conversion.