Also returning to the starting line up is fellow Scotland international Alasdair Strokosch who starts at blindside with Brett Deacon moving across to number eight.
Able to call upon Hamilton's services for the first time, Head Coach Bryan Redpath explained what he (Hamilton) will bring to the side.
"Jim's another lineout option. He's obviously a big man, he's called lineouts for Scotland and Edinburgh and he takes a little bit of heat of Browny and puts a bit of heat on them as well."
"He's a big angry man. He's 130kgs which hopefully he's going to throw around. He's here to be physical and that's what we want."
Talking to the media ahead of the game, Redpath was quick to pinpoint the key area of improvement from the first two games.
"Too many individual errors. I think 25 against Exeter and 17 last Saturday. We're creating a huge amount of scoring opportunities but not finishing them off."
"We've been far better than we have been previously defensively and in terms of discipline but need to show a little more patience and composure."
"Irish are a good side. We're playing away from home, four yellow cards last year down there. They have a dangerous back three. You kick poorly, you kick loosely and you're going to get punished."
"We have to have a very strong disciplined game to play against them. It's a big challenge for us this weekend. But we need to be up for it. It's about us and not all about the opposition."
Charlie Sharples; James Simpson-Daniel, Mike Tindall (capt), Eliota Fuimaono-Sapolu, Lesley Vainikolo; Nicky Robinson, Rory Lawson; Alasdair Dickinson, Scott Lawson, Pierre Capdevielle; Jim Hamilton, Alex Brown; Alasdair Strokosch, Andy Hazell, Brett Deacon
Olivier Azam, Nick Wood, Rupert Harden, Dave Attwood, Luke Narraway, Dave Lewis, Tim Taylor, Tim Molenaar