The Italian did not attend Friday's press conference ahead of City's clash with Tottenham Hotspur at the Etihad Stadium in the Premier League on Sunday.
"People make a great deal of it but he's fine," said Platt. "It's not the first time he's reacted in that way (after the Ajax game on Tuesday when he shouted at the referee), not necessarily at Manchester City but even as a player.
"What he does, he has a great desire to win football matches, so his concentration is on winning matches. It's not, 'Oh, what's going on here, how can I stop this, what can I do?'
"He's not cold, he's not manipulated, in any way, he doesn't look at strategy with you boys (the media). A lot was made the other week when he came in here – he didn't rant and rave [about Monaco], even though that was the way people wanted him to say it."
City are currently third in the Premier League table with 22 points from 10 matches, two points behind leaders Manchester United.