Benetton had prop Ivan Nemer carried off with an injury early on and soon after Connacht got the scoreboard ticking over when fly-half Ioane dived over in the corner after the ball went quickly through the hands. Cathal Forde added the extras.
The score was followed by a television match official (TMO) review which resulted in visiting centre Malakai Fekitoa receiving a yellow card for a shoulder to the head of Tierney-Martin in the build-up to the touchdown.
Jacob Umaga got Benetton off the mark with a penalty but after a fine flowing attack after a line-out midway through the first half Ioane off-loaded to Naughton who ran in for his side’s second try as the hosts made use of their one-man advantage.
Connacht wing Chay Mullins was then sin-binned for a deliberate knock-on, before Onisi Ratave went over in the corner but a TMO review revealed that the wing had a foot in touch before grounding the ball over the line.
The Italian side got off to a flying start in the second half when Lynagh nipped in to score in the 42nd minute after a darting run and off-load from Tommaso Menoncello.
Benetton flanker Michele Lamaro then became the third player to be yellow-carded, this time for a high challenge, after a TMO review.
The home side made good use of their numerical advantage when a quick kick led to Tierney-Martin barging over beside the post from close range, Forde kicking the additional two points.
Replacement Fiachna Barrett, making his URC bow off the bench, got the ball down but the try was disallowed for a foul in the build-up.
The bonus-point try was not long in arriving however as with six minutes remaining, number eight Jansen gathered the ball from the scrum and burrowed through the Benetton defence to score.
A late try from Alessandro Garbisi, converted by Umaga, proved to be a consolation.
