Italian skipper Sergio Parisse also reached his century of caps in the same game and the experienced duo provide a solid forward platform for head coach Jacques Brunel. Both will be key men on Saturday alongside Zebre lock Marco Bortolami, who will make his 100th Italian appearance at the Millennium Stadium.
James said: "I've played against Castro quite a lot and we know each other inside out, I suppose you could say we're mates!
"He is a big unit and has plenty of experience. Alongside Parisse, they are the influential players in their pack so if we stop them, then we will do well."
With Gethin Jenkins not involved against the Italians, James gets an opportunity to start and continue the fine form he has shown with club side Bath. The English side are showing up well in the Aviva Premiership and sit in third place domestically behind Northampton Saints and Saracens at the top of the table.
"Gethin is probably disappointed not to be involved but I have got the opportunity," said James.
"We've been going well at Bath and we have been dominant up front in a lot of matches. We are getting the results this season at Bath but we put the hard work in last year. We have gone on from there and worked hard all summer and now the performances are coming.
"It's a lot easier to play in a good team and hopefully I can slot back into the Welsh pack this weekend. We trained hard as a squad last week and this week and it's worked well for us.
"I just want to go out and perform well for the team."
There are still a limited number of tickets available for Wales vs Italy at the Millennium Stadium on Saturday, February 1. To get your tickets go to www.wru.co.uk/tickets.