'I can say without any shadow of doubt that Shay Given is the best goalkeeper in the world,' Murphy said.
Related ArticlesWorld Cup play-offs: Ireland to play FranceIreland tipped to upset play-off oddsRep of Ireland 0 Montenegro 0Capello honest to a fault?How the World Cup play-offs workLippi counts his omens'I just think that Shay has got everything you need to be successful as a goalie and his attitude to his job are second-to-none. He really does tick all the boxes as a goalkeeper for both club and country.
'The moment that Shay crosses that white line whether it is for a training session or a proper game his concentration is purely focused on keeping that ball out of the net.
'When you train with him and play with his as closely as I have with Ireland you really appreciate what a great professional he is because he always does everything in his power to improve himself.
'OK, I know I haven't worked with the likes of Buffon, Casillas or Cech but I do believe there is no one better on earth than Shay Given which is why Mark Hughes took him to Man City last season.
'Shay is great in training with me and does his best to help me along. When he sees you do something that he thinks is wrong then he will mention it to you but you can learn by just watching him in action.'
The international colleagues will go become rivals at Eastlands on Wednesday when the Championship side try to spring a surprise on the well-to-do Premier League club.
'It will be great to be on that big stage at City and we know it will be tough because Mark Hughes will put out all his big-hitters because they want to win something this year but we're not daunted by going there,' Dublin-born Murphy, 28, added.
'We're really excited about taking on Man City. It will be a bonus for us because we have had to get through some tough games in the previous rounds so this will be a reward for us. This season is all about the league for us so we will go there and enjoy it and we certainly won't be overawed by the occasion.
'People are going to be surprised that we beat Newcastle United but we fully deserved to beat them just like we did when we beat Sheffield United and we are determined to give a good account of ourselves.'
The former Tranmere, West Bromwich Albion and Sunderland goalkeeper continued: 'I'm not sure about why we have been doing so well but the team spirit is great and the manager has got it right formation-wise and player-wise.'
'We looked comfortable throughout the game against Newcastle who had loads of players with Premier League experience. We just saw it as another win because we know we have to pick up points.
'A lot of people will be pleasantly surprised by what a decent footballing side we are. We have brought in some good players and they have complemented the ones that have been here for quite a few years. They are all comfortable on the ball and a lot of teams don't want to come to our place and play because it is a tight pitch.
'Our lads will know they have to be at their best to beat Shay but who knows what will happen on the night but you never know what could happen.'