"We made them look quite ordinary today," Hughes told the BBC. "In terms of chances and general play, we were always looking positive.
"It was just a shame we didn't take our chances. Box to box we were excellent but we needed that killer instinct."
Hughes was fired by City in 2009, and his replacement, Roberto Mancini, was fired at the end of last season before Pellegrini was handed his first job in England.
City made six changes ahead of the start of its Champions League campaign on Tuesday against Viktoria Plzen.
Pellegrini opted to change his strike pairing and hand a debut to Stevan Jovetic and a first start to Alvaro Negredo, with Sergio Aguero and Edin Dzeko dropping out.
Javi Garcia again failed to impress in central defense after surprisingly replacing Joleon Lescott, while James Milner, Jack Rodwell and Samir Nasri came into the side with little effect.