Lambert was dumped by the Reds as a teenager.
"I think Rickie is a terrific player," said Rodgers. "People look back now and say it was a mistake (to let Lambert go), but there may have been something at the time that was a factor.
"He just might not have been ready for what Liverpool was at that time, but there is absolutely no doubt within development it cannot just be about what the player is now. With young talent you always have to look at what they could be.
"You see so many young British players who are thrown to the garbage because maybe they are not strong or they are not quick when they are going through growth spurts. The emphasis at younger ages should be technique. But I have been a big admirer of Rickie.
"I sent him a message, a fax, when he made his England debut as I know he is a big Red. I sent it on behalf of the club and all Kopites. He is a Kirkby boy and I was just wishing him well, saying we were all proud of him playing for England. Hopefully, now he won't score against us!"