Jayden Hayward’s last-gasp penalty sealed a famous comeback win for Benetton Treviso against second-placed Connacht, seriously denting their hunt for a Guinness PRO12 home semi-final, but ensuring a first ever top-four finish for the Irishmen.

Peter Robb’s second-half score and John Cooney’s boot looked to have ensured Connacht kept pace in their quest for a home play-off, but Hayward banged over his penalty from almost 50 metres to claim Treviso’s first win over an Irish province since 2013

Pat Lam’s side looked untroubled as they racked up two scores inside 15 minutes through Fionn Carr and Rory Parata, but the Italians struck back with two first-half scores of their own – through No.8 Abraham Steyn and Luca Morisi to leave the sides poised at 14-12 going into the break.

And it was Marius Goosen’s side who struck first after half-time, their dominant front-row milking a penalty try that Hayward converted.

Connacht go into next week’s critical clash with Glasgow Warriors knowing only a win will secure a home semi-final and most likely rueing their ragged finishing though doubtless thankful their losing bonus point has secured a first ever play-off spot.

It was a frenetic start in Treviso, both sides looking to run the ball from all corners of the track in almost perfect conditions for champagne rugby.

Treviso were playing with real positivity, but their inaccuracy cost them after six minutes when they were penalised for coming in from the side in sight of the Connacht line.

Their sloppiness at the breakdown handed Lam’s side a perfect attacking platform as Jack Carty put them in the corner and after two minutes of sustained pressure, found the breakthrough.

Cooney picked out Jake Heenan close to the ruck, the flanker’s instinctive give and take putting Parata under the sticks. Cooney knocked over the simple conversion for a 7-0 lead after 11 minutes.

Carr’s length-of-the-field break almost immediately led to a second Connacht score, but the winger did not have to wait long to cross – latching onto a perfectly weighted Carty grubber and dotting down. Cooney converted.

It looked ominous for the Italians, but Morisi hit back with a try midway through the half after picking a sharp supporting line – but Hayward was off target with the kick.

Steyn then showed all his strength to bring Treviso right into the match, a huge fend on Tiernan O’Halloran left him in space and he then powered over for his side’s second within five minutes of their first.

Hayward shook off his earlier miss to bang over a touchline conversion to leave the sides poised at 14-12 going in for the break.

Treviso had been beginning to turn the screw at scrum-time as the first-half wore on and they made that advantage count five minutes into the second-half, bludgeoning Connacht into submission and forcing a penalty try which Hayward converted to put Treviso ahead for the first time.

Lam’s side could not be shackled for too long and despite Connacht consistently getting bettered at set-piece, the Irishmen’s free-flowing approach eventually paid off.

O’Halloran’s 40 metre break put Connacht deep into Treviso territory and they swept across the field in a lovely team move before working a blind side to perfection, allowing Robb to finish well in the corner. Cooney’s conversion did not look the prettiest, but it sneaked over to restore their lead.

It was a scrappy second half and though the likes of Carr continued to threaten, Treviso defended stoically throughout and when they won another scrum penalty on 82 minutes, Hayward showed nerves of steel to send the Italians into euphoria.

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