Esteban Cambiasso gave the Coppa Italia holders the lead in the first-half, but they would concede twice in a three-minute spell after the break, and the ex-Roma boss has spoken of his regret at his team coming slowly out of the blocks following the interval.
"We needed to pick up points and looked to succeed in that aspect, but in the second half we conceded two counter-attacks straight away," said Ranieri to Sky Sport Italia after the match.
"We should've stayed compact as we were in the first half, but now we must remain calm and continue working hard, because there’s a lot to do," he continued. "I requested that the team keep their shape. Now, we want to react and get back on top."
Despite a penalty proving to be the decisive goal in proceedings, Ranieri accepted the call to award Catania a spot-kick, and also praised the performance of referee Daniele Orsato.
"The penalty was understandable, as it's difficult for the referee to see the goalkeeper had taken his hands away before Gonzalo Bergessio fell. In my view, he officiated [the match] well."
Inter drop to 17th in the Serie A standings after their latest defeat, having picked up just four points in six league matches.
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