The Dragons kept hold of second place in Group D thanks to Friday’s 1-0 win away in Georgia but, with the Irish just one point behind, there’s still all to play for in Cardiff.
“We know what the Republic are good at,” Coleman said. “But this is the last game of the campaign, all or nothing for both teams.”
The last match between the two sides, a 0-0 draw in Dublin, saw Ireland captain Seamus Coleman suffer a broken leg from a challenge with Neil Taylor.
“Even without the unfortunate incident in Dublin with Tayls and Seamus, this was always going to be a game where there will be two teams locking horns,” Coleman added.
“But even before what happened (in Dublin) it was a physical game and we expected it to be. We were all absolutely devastated at what happened.
“There will be lots of contact in the game, it will be physical, good players, and not much in it. We’re just going to go with our game-plan and make sure we’re 100 percent focused on doing what we’re good at.”