Victor Matfield said he was the best player he had ever played against and even the Sunday Times' Stephen Jones acknowledged him as 'one of the great players of history'.
Brian Moore tweeted in tribute that O'Connell was not only a great player but 'an equally good bloke'. One of the responses pointed out that he was 'a legend. And not just to his compatriots'.
How are international observers absorbing the reaction of his retirement from the game?
Good luck @Paul_OConnell with the retirement. Pleasure to play with you, not so much against! Crazy eyes in your team talks! #itsamaul
— Adam Jones (@adamjones3) February 9, 2016
Sad to see @Paul_OConnell retire, but what a legend on and off the field. Pleasure to share the same field with and against him.
— gethin jenkins (@gethinjenkins1) February 9, 2016
Chapeau to @Paul_OConnell on an outstanding career and for being an equally good bloke.
— Brian Moore (@brianmoore666) February 9, 2016
Congratulations on an amazing career... What a contribution to the game #Legend @Munsterrugby @IrishRugby @lionsofficial
— Mark Cueto (@Mark_Cueto) February 9, 2016
Sad to hear the great Paul O'Connell has retired from rugby. What a player & person. Huge name to play with or against#truegreat
— Nick Easter (@nick_easter) February 9, 2016
Sad to see a legend of @IRFURugby & @lionsofficial retire due to injury. @Paul_OConnell it was a pleasure to play against and watch you. #?
— Tom Voyce (@TomVoyce) February 9, 2016
@brianmoore666 @Paul_OConnell legend, not just to his compatriots
— peter simmons (@Mr_Peteroy) February 9, 2016
#NumberCrunchTuesday kicks off with figures from a wonderful 15 years @Munsterrugby, @IrishRugby & @lionsofficial pic.twitter.com/ouYiJPRlTg
— Sky Sports Rugby (@SkySportsRugby) February 9, 2016
Heartbreaking for the truest gent of the game to bow out like this. Rugby fans everywhere salute you @Paul_OConnell https://t.co/oKj1nDX5M4
— Laura-Jane Jones (@MissLJJ) February 9, 2016
Enjoy your retirement, @Paul_OConnell - it's been a privilege #ThanksPaulie pic.twitter.com/ImGFKHt2bR
— British&Irish Lions (@lionsofficial) February 9, 2016