Platt delighted with Dzeko impact
The Bosnia-Herzegovina forward stepped off the bench to inspire a dramatic turnaround in fortunes at West Bromwich Albion on Saturday.
Dzeko struck two late goals, the second in added time, as ten-man City came from behind to win 2-1 and end the hosts' perfect Premier League record at The Hawthorns this season.
It was sufficient to preserve City's unbeaten league start and ensured they avoided losing ground to leaders Chelsea and rivals Manchester United.
"If you look at Edin Dzeko's career with Manchester City he has scored a lot of 'heavy goals' - goals that are very important," Platt said of the striker, who has scored six times for City so far this season.
"He scored one against Blackburn two seasons ago that more or less got us Champions League football. He has been a threat all season and his form has been very good."
At The Hawthorns, James Milner's sending off midway through the first half had appeared to hand the advantage to the Baggies and they took the lead through Shane Long's close-range strike.
However, the response from Mancini's side was befitting of their status as champions as Dzeko levelled with an 80th-minute header before stunning the Baggies, who had won their previous five home league matches, by clinically finishing off a swift counter-attack.
"I don't think you win any championships without that spirit," Platt added. "Last season we won our last six matches. There were games we didn't play particularly well in but won."