The home side racked up seven tries in total and fly-half Dan Biggar was successful with six conversions, while Treviso's Dean Budd saw red for a swinging arm tackle late in the game.

Evans began the scoring before Dan Baker and Owen Watkin crossed before half time.

Olly Cracknell and Hanno Dirksen scored in the second half, before Budd saw red and Evans and Ben John wrapped up the points for Ospreys.

The home side were ahead after eight minutes as they worked the play out to the left for Evans to step inside and cut through three missed Treviso tackles and run in from outside the 22, Biggar adding the extras.

Treviso cut the Ospreys lead five minutes later as Jayden Hayward slotted between the posts.

But the home side extended their advantage after 20 minutes as Baker popped out the back of a rolling maul to pile over in the corner for his fifth Guinness PRO12 try of the season, and Biggar was again successful with the conversion.

Ospreys were rampant and moments later came close to a third try, but Rhys Webb was judged not to have grounded the ball just short of the try line.

They soon had a third though as Webb combined with Biggar from the scrum to feed Watkin who drove over from five yards out and Biggar did his duty from the tee.

Shortly before half-time there was a significant delay as Treviso hooker Ornel Gega went down with a head injury when attempting to tackle Dirksen.

He was taken from the pitch on a stretcher but gave a thumbs up to teammates and the crowd as he was carried off.

Life got even harder for Treviso early in the second half as Robert Barbieri and Dean Budd were sin-binned within three minutes of each other, reducing the visitors to just 13.

They were made to pay too as Cracknell crossed the line for his first ever Ospreys try, clinching the crucial bonus point, with Biggar's boot again successful.

And it got even better for Ospreys as Dirksen touched down for his side's fifth try of the game on 56 minutes, finishing off a fantastic team moved that started in their own half and crossed the width of the field.

Biggar missed the conversion but the home side's lead was now a healthy 30 points.

Treviso narrowed that gap after 65 minutes with a set play from their line out leading to Alberto Sgarbi crossing from 20 yards out and Sam Christie then converting.

But the Italians' misery was complete with five minutes to play as the returning Budd saw red for a dangerously high tackle and swinging arm.

The home side then added insult to injury as Evans bundled over for his second try of the game in the left corner, which Biggar again converted.

And Ospreys scored a final try in the final minute as Biggar's deft kick through was collected by John for a simple finish and another conversion from the fly-half.

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