Liverpool famously decided not to sign the Portugal superstar when he was 18, and he went instead to Manchester United for £12m, where we won three Premier League titles and one Champions League before becoming the world's most expensive player after signing for Real Madrid.
The Reds, according to their boss at the time, Gerard Houllier, did not have the budget to afford the teenager, and had already signed Kewell in a £5m deal from Leeds.
Kewell, now manager at League Two Crawley Town, believes the Frenchman made the right call 14 years ago not to sign the future Ballon d'Or winner.
He said: "I don't know if you can say that [on Liverpool nearly signing Cristiano Ronaldo].
"I mean back when I had signed for Liverpool, I think I was the number one person to go round in that year, so I think he (Gerrard Houllier) made the right decision.
"In hindsight, yes, you could turn around and say a lot of things, there's a lot of great players that have gone elsewhere that have never been signed.
"I think recently the biggest one was Raul. Raul got let go by Atletico Madrid and then look where he went to. How do you say that?"