The former Ireland captain was speaking on Newstalk Breakfast on Friday
Paul O'Connell has praised the Munster team for their performances this season and has admitted they have exceeded expectations in what has been a difficult year for the southern province.
Speaking to Shane Coleman on Newstalk Breakfast, the former Ireland captain is expecting Munster to be pushed to the brink when they face English and European champions Saracens next weekend saying: "I wouldn't be optimistic about winning, I'd be optimistic on getting a big performance from Munster.
"I think if Munster didn't win another game for the rest of the year, I think the season would have still been a great success. What they've managed to do this year has been absolutely phenomenal and obviously in really difficult circumstances as well.
Munster's Billy Holland celebrates victory over Toulouse. Image: ©INPHO/Dan Sheridan
"Saracens play in kind of a similar way to Munster but they're a lot further down the track from us in terms of their development and they've an awful lot of first choice English internationals in their side as well so it's a really, really, big, big challenge for Munster.
"It's great to be back in a semi-final playing in Dublin at the Aviva as well. There's going to be a mass exodus from Limerick, Cork and all of Munster so it's really exciting times," he added.
The Irish legend stepped away from the game after failing to recover from a hamstring injury he sustained at the 2015 World Cup but he is content in retirement, saying: "Look, I retired when I was 35. Some of my good friends had to retire a lot earlier with injuries.
"I think when you manage to get as much out of it as I did you kind of retire a little bit more satisfied maybe than other people do.
Ireland's Paul O'Connell leaves the field injured at the 2015 RWC. Image: ©INPHO/James Crombie
"As well as that, my body is in fairly good shape. I just look at games now and I just know there's no way my body could take it any more.
"I think when you're in that position and you're happy to be retired, you're able to enjoy it more and enjoy being a fan more. I enjoy taking Paddy to the games. I enjoy the commentary with the BBC very much - it's a really good experience," he added.