The 29-year-old’s magnificent form for Munster in recent Heineken Cup matches made his international return inevitable, however, and he has replaced Wasps’ Johnny O’Connor at openside.

O’Connor must settle for a spot on the bench with O’Sullivan indicating Wallace’s abrasive style will be required when the rugged Italians run out at Lansdowne Road on Saturday.

“We’ll be playing against a pretty hard pack on Saturday. There will be a lot of close quarter hand-to-hand combat so we’ve picked a back row to meet that,” he said.

“David has played particularly well in the last month and has forced his way into a very difficult department of the team.

“Back in the autumn he didn’t get into the squad because he wasn’t in the Munster team. His first Heineken Cup game was after the autumn squad was picked and since then he’s got better and better.

“He’d been dogged by injury and his form wasn’t great earlier in the year. Ball carrying has always been a strength of David’s game.

“But there are other important aspects to playing back row, such as being involved at the breakdown and linking up with the back line and he’s improved in these areas.

“His work rate has gone up dramatically. Against Sale a couple of weeks ago he had six poaches which is a colossal amount of work on the opposition’s ball.

“This was an area he hadn’t focussed on before. We talked to him at length about it and he’s worked on it.”

Wallace is joined in the side by Munster colleague Jerry Flannery who has edged Ulster’s Rory Best for the hooking duties.

Flannery made his Test debut as a substitute against Romania in November when Shane Byrne was first choice but the veteran Saracens front row was axed last week.

“The hooking position was a tight call between Jerry and Rory. When we picked the team in the autumn Jerry was on the bench for Munster,” said O’Sullivan.

“But then Frankie Sheahan got injured and Jerry started playing for Munster. He came off the bench against Romania and has had a really good run of form since.

“He’s edged Rory with his performances in the Heineken Cup. He’s our form hooker at the moment.”

Lions Brian O’Driscoll and Paul O’Connell are back after missing the entire autumn series through injury and O’Sullivan warned Italy his talisman duo are “fired-up“.

“Brian and Paul are two world-class players, two captains and two Lions who were missed during the autumn. We missed their performances on the field and their leadership,” he said.

“It’s good to have them back in such a rich vein of form as well. Their return is a good boost to the squad.

“Now we have to make the best use of them. They’re pretty fired up for the Six Nations.”