Wales did not let Ireland into the game – Best
Rory Best conceded Ireland had no answer to a dominant Wales display as Warren Gatland's side sealed Grand Slam glory in the Six Nations with a 25-7 win in Cardiff.
Wales took a second-minute lead through Hadleigh Parkes' try and Gareth Anscombe added 20 points from the tee, with the 2018 champions unable to get on the board until Jordan Larmour touched down beyond the 80th minute.
Gatland consequently became the first coach to win the Grand Slam on three separate occasions.
In his final Six Nations match, Ireland captain Best felt his team were unable to respond to the early blow Wales dealt them.
"Wales had a cracking start and they delivered a game. They're a very good side, a very determined side. They're very hard to beat at the Principality Stadium," Best told the BBC.
"We just couldn't get a foot in the game. Our set-piece wasn't up to the standards we expect and they came after us. They really put a lot of pressure on us and we struggled to respond."
Congratulations @WelshRugbyUnion on a fantastic performance and Grand Slam.— Irish Rugby (@IrishRugby) March 16, 2019
Thank you to all our supporters who are with us through the good days and the tough ones.
A very tough day today. #TeamOfUs #WALvIRE pic.twitter.com/vb6HdFoJJA
Ireland overcame number-one ranked New Zealand in October but defeat to Wales was their second loss of the competition, having gone down 32-20 to England in their Six Nations opener.
Best, competing in his final match in the competition, was not too concerned about the recent setbacks, despite them coming in a World Cup year.
"It's a very competitive Six Nations. We've lost to two very good sides. We'll have to go away and address why we lost and how we can get better," he said.
"We always strive to get better. We haven't done that. We've been a little inconsistent in these championships. We'll have to dust ourselves off and try to finish the calendar year strong.
"It's very disappointing. We can talk about the aftermath later on – you just have to give credit to Wales, deserved Grand Slam winners. We just have to congratulate them."