Munster’s performance against Ulster was "not good enough" and must not be repeated if they are to beat Glasgow in tonight's RaboDirect PRO12 semi-final, according to Peter O’Mahony.

O’Mahony, who will miss the semi-final (kick-off 7.35pm) as he recovers from the shoulder injury sustained in Munster’s Heineken Cup quarter-final win over Toulouse, said travelling to Scotstoun should not daunt Munster, all the more so since his side won there during the regular season.

“That was a hard-fought win that we got over there, but it is one of the toughest places to go and play, especially in the Rabo," he told RTÉ Sport. 

“You go over looking to put yourself in the best position to be in with a [chance of a] win by the end of the game. That’s what the boys have to do.”

O’Mahony described Munster’s performance in the 19-17 loss to Ulster as “not good enough” and said that more will be required to beat Glasgow.

“No-one will know that better than the lads that played,” he said.

“It just wasn’t a good enough performance. I know it’s very easy for me to sit in the stand and say that, but, as I say, the boys who took the field will know that better than anyone else and will be looking to put it right at the weekend.”

“You’re dissecting it a bit as it goes, and you’re probably calling calls that you hope that they’re calling on the pitch" - Peter O'Mahony on watching from the sidelines

He said that Munster players would not need any further motivation for what he described as the “biggest game of the year in the Rabo”.

“If the semi-final of a big competition like this doesn’t get you motivated, you’re probably in the wrong sport,” O’Mahony said.

“You’re certainly at the wrong club.”

O’Mahony admitted he was not a great a great spectator: “I’d probably put an apology into anyone who was around me at the time”, and gave some insight into the frustration of watching from the sideline.

“You’re dissecting it a bit as it goes, and you’re probably calling calls that you hope that they’re calling on the pitch. But there’s nothing you can do; it’s irrelevant, really.”

He hailed the influence of departing coach Rob Penney on Munster, suggesting he had introduced new facets to Munster’s game, and that his Pro12 coach of the year award was well deserved.

“He’s probably put an extra feather in the Munster rugby cap” he said. “We’d probably [have] been seen as a big up-front team, but we’ve shown at times this year that we can play some nice rugby, and play a bit of ball.”

LIVE RUGBY: Listen to live Radio commentary of Glasgow v Munster, RaboDirect PRO12 semi-final, kick-off 7.35pm (Friday 16 May, RTÉ 2FM and RTÉ.ie, 7pm).