The former Manchester United manager made the comment in his autobiography, but Rodgers insisted the criticism was unjustified.
Rodgers told talkSPORT: "I think everyone who's seen the comments will think they are harsh.
"I've watched Gerrard for many years and recognised he's a top player, but it's only when you come in and work with the man that you realise how professional he is on a daily basis.
"His performance level at 33 years of age shows he's a top, top player. He's a great talent, a wonderful player and I don't think anyone could argue against that."
Joey Barton has also defended the Liverpool midfielder, claiming Gerrard was a better player than Ferguson's long-time captain Roy Keane.
He said on Twitter: "On a serious note. Gerrard for me, was better than Roy Keane. At one stage he was up there with the best midfielders in the World.
"Lucky enough to have Played against them both on number of occasions. Steven Gerrard streets ahead IMO. Keane was v good but SG better...
"People forgetting Keane played with the best in the World at United. He wasn't same player with the Republic. Was he?"
Ferguson was also dismissive of Gerrard's fellow England midfielder Frank Lampard, saying the Chelsea man was in his eyes not "an elite international footballer".
Rodgers was also full of praise for his in-form striker Daniel Sturridge, whom he reckons can become one of the best in Europe.
He said: "He's been brilliant. He's come here in January with a point to prove. He's very hungry and his goals per game ratio has been remarkable.
"Daniel's a player who produces. He's a natural goalscorer, but he's got so many other things to his game, pace, power and great feet. I think in the next few years he could be one of the top strikers in Europe."