The Italian claimed that Terry made a 'big mistake' in speaking out but never contemplated dropping the Chelsea defender, who he sacked as captain in February following allegations about his private life.
Terry will play in the Group B encounter against Slovenia which England must win following disappointing back-to-back draws with the United States and Algeria.
Elsewhere, Capello claims the mood in the camp is good and that his heavily-criticised players are ready to live up to expectations.
Asked about his relationship with the players, Capello replied: "Really good, because every time when I speak with the players they follow me.
"The players are happy. They trained very well.
"I think it's normal to have pressure at the moment. We have a play-off to be in or out. We have to win."
Meanwhile, Capello has backed mis-firing striker Wayne Rooney to rediscover his best form following two lacklustre displays in South Africa.
"I spoke a lot of time with Rooney and he is an important player for us," he explained.
"Sometimes the pressure is so big, also for the important players. He improved in the last three days during training. I am sure on Wednesday he will play really well."