The Welsh team-mates will come face-to-face with Giggs down United's left and Simon flying up and down our right.
In-form Simon, with four goals in eight games for Spurs and Wales this season, was a huge fan of the wing wizard when he first burst onto the Premiership scene in the early 1990s.
Now, of course, Simon is very much seen as the future of his country's football alongside the likes of Craig Bellamy, Robert Earnshaw, Jason Koumas and Daniel Gabbidon.
Simon revealed: "When I was younger Ryan was a hero of mine. He was such an icon when he was younger, especially to the young players and still with Wales, everyone looks up to him and he sets the standards we all want to follow.
"On Saturday it will be hard, but I'm looking forward to it. It's the sort of test you want as a footballer. I'll do what I can, we'll see what he does and hopefully we'll come out on top."
Simon is wary that we need to be defensively solid at Old Trafford, especially in the early stages.
He added: "I think we have to be defensive-minded at first. You can't go up there expecting to dominate the game but we've got pace within the side and we can break on them, so hopefully we'll be able to do that.
"First of all we have to be tight as a team, stay solid and see where we can go after that."
Simon Davies is relishing the prospect of facing his boyhood hero Ryan Giggs at Old Trafford on Saturday.