It was only their fourth win of the current campaign and Rowland Phillips' side were fully deserving of the result after first half tries from Nicola Cattina and Gabriel Pizarro saw them take a 15-3 interval lead.

With David Wallace making a very welcome return to action in the 57th minute, Munster upped their game and closed the gap down to four points to set up a dramatic final seven minutes.

However, over anxiousness from the visitors and some stout defending from Aironi denied them a last-gasp win and the Italians celebrated the biggest scalp in their two-year history.

It was Wallace's seasonal debut for Munster and it came almost seven months after he sustained a World Cup-ending knee injury during a warm-up game against England at the Aviva Stadium.

Speaking after the game, the returning back rower told the Irish Examiner: "I was delighted to get 25 minutes under my belt. I really had no inkling as to what way it would go.

"But I felt comfortable out there, more comfortable than I thought I would feel. Looking forward, I have no lofty goals for myself because I don't want to be disappointed.

"It's going to take a lot of time and a lot of rugby, and obviously a lot of patience before I get back to where I was. But today was the first step, hopefully of many."

This encounter, which was originally due to take place last month, burst into life in the seventh minute when flanker Cattina won the race to Luciano Orquera's grubber kick. Orquera increased his influence by adding a penalty on the quarter hour mark.

Scott Deasy hit back with a long range penalty for the men in red, however Aironi grabbed a second try before the break.

Poor defending from Munster allowed the hosts to string the passes together and centre Pizarro snuck through for seven-pointer.

Both sides were clearly missing the influence of their Six Nations-tied players, although Aironi managed to add another three points to their total through the boot of Orquera.

Munster head coach Tony McGahan sought to change things around by introducing Ian Keatley and the experienced trio of Marcus Horan, BJ Botha and Wallace.

With their pack now reinforced by fresh legs, Munster forced a penalty try on the hour mark after a series of scrums near the Aironi whitewash. Keatley added the extras for an 18-10 scoreline.

A costly penalty led to Orquera putting 11 points between the sides and that proved to be a vital score despite a late rally from McGahan's charges in the closing stages.

Centre Lifeimi Mafi sprinted in by the posts in the 73rd minute, after gathering a pass from Wallace, and with Keatley converting, the heat was back on Aironi.

Munster's final opportunity to snatch the victory saw Keatley hang up a cross-field kick for fellow replacement Luke O'Dea, but the ball instead bounced into touch.

Made to pay for a sluggish start, the visitors' improvements in the final quarter were a case of too little, too late as they lost for the first time since their December derby defeat to Ulster at Ravenhill.