The Newport Gwent Dragons flanker-cum-second-row is the only newcomer in Rob Howley’s squad to face Ireland at the Millennium Stadium.
Wales captain Warburton has been impressed by Coombs regional form.
He has been impressed by the way the 28-year-old has adapted to life in the national set-up and having gone up against him in the RaboDirect PRO12 he is relishing becoming teammates.
“You can tell he (Coombs) is dying to get on the pitch,” said Warburton.
“I think he is one of those players who I don’t think it will affect him too much. I think he will take it all in his stride.
“He seems very confident and ready for the game on Saturday.
“He is a very difficult player to play against. He has played exceptionally well over the past few months, and I am looking forward to packing down with him.”
There had been a suggestion that Rob Howley would select Warburton in tandem with Justin Tipuric in the back-row.
But the Wales interim head coach has opted to keep Warburton on the openside flank, with Aaron Shingler starting on the blindside.
“The back-row is the same we finished the autumn with, so there is that consistency there,” added Warburton
“I think with the three selected we do cover all the bases in terms of the balance.”
You can follow all of the action for Wales v Ireland at http://www.wru.co.uk/live