Wales will attempt to shut down Ireland halfback stars Johnny Sexton and Conor Murray in Saturday's Six Nations clash in Dublin.
Gatland, who this week becomes only the second coach after New Zealand World Cup winner Graham Henry to clock up 100 Tests for one country, knows that keeping them quiet will be key to victory hopes in Dublin.
"We've got to attack them," said Gatland, who has made three changes from the side beaten by England 10 days ago, calling up fit-again fullback Leigh Halfpenny, wing Liam Williams and outhalf Dan Biggar.
“We have had some pretty good success not allowing Johnny too much time and space on the ball. Our line-speed defensively has got to be good.
“We have got to put Conor and his kicking game under pressure. We have to be prepared to be pretty physical against them.
“We have got to be physical against them up-front and stop the running power of someone like CJ Stander, and stop allowing Murray and Sexton to dominate the game. If we can do that, we have got a chance.
“They are comfortable playing through lots of phases, they’ve got an excellent kicking game, their nine and 10 combination is probably one of the best in world rugby. We’ve got a job to do to try and shut them down.”
Many pundits feel the championship is hurtling towards a title showdown between England and Ireland at Twickenham on March 17th, with both sides unbeaten after two rounds of the championship.
Asked, though, if he thought Ireland were the strongest team in the tournament, Gatland added: “No. England are a tough outfit. Ireland ground out a win in France.
“You’ve got to keep your discipline against Ireland. Our discipline has been excellent in the first two games.
“We’ve got to make sure we don’t give Ireland an opportunity to kick to the sidelines by giving away penalties and execute their driving lineout, which is pretty effective, and allow Johnny Sexton to keep their scoreboard ticking over with three points.
“That’s what they do. They play through lots of phases, but we’ve conceded the least points in the competition so far.
"Andy Farrell [Ireland defence coach] won't be happy with Ireland conceding 19 points against Italy. Two or three of Ireland's tries against Italy were from turnover situations and an interception.
“We’ve got to make sure we don’t get caught up in that, keep our patience defensively and our discipline has to be good. They are a quality side that are hard to break down.”
Biggar has shaken off a shoulder problem suffered a month ago that ruled him out of Wales' opening two games against Scotland and England, returning to the starting line-up instead of Rhys Patchell, while Halfpenny has recovered from a foot infection and replaces Gareth Anscombe, with Saracens wing Williams in for Worcester's Josh Adams.
Both Patchell and Adams drop out of the matchday 23, and Northampton wing George North remains on the bench, with Gatland opting for a back-three of Halfpenny, Williams and Steff Evans.
WALES (v Ireland): Leigh Halfpenny (Scarlets); Liam Williams (Saracens), Scott Williams (Scarlets), Hadleigh Parkes (Scarlets), Steff Evans (Scarlets); Dan Biggar (Ospreys), Gareth Davies (Scarlets); Rob Evans (Scarlets), Ken Owens (Scarlets), Samson Lee (Scarlets); Cory Hill (Dragons), Alun Wyn Jones (Ospreys capt); Aaron Shingler (Scarlets), Josh Navidi (Cardiff Blues), Ross Moriarty (Gloucester).
Replacements: Elliot Dee (Dragons), Wyn Jones (Scarlets), Thomas Francis (Exeter Chiefs), Bradley Davies (Ospreys), Justin Tipuric (Ospreys), Aled Davies (Scarlets), Gareth Anscombe (Blues), George North (Northampton).
