The Real Madrid stopper had a difficult night for the European and world champions and Maradona pulled no punches when commenting on the veteran's performance in the World Cup Group B clash.
"He had the worst game I've ever seen in my life... and it reminds me of what my friend [Jose] Mourinho said to everyone," Maradona told Telesur.
"He said Casillas wasn't the right keeper and he paid for that. He had to leave Madrid, but it turns out he was right."
Casillas played every Copa del Rey and Champions League match for Los Blancos last season, but Diego Lopez was preferred in the league.