Mayor de Blasio is one of the city’s biggest Boston Red Sox fans — but on Wednesday he couldn’t hide his disappointment in his favorite team.

“My faith has been shaken,” said de Blasio, when asked at Wednesday night’s Mayoral debate at the CUNY Graduate Center about reports that team officials admitted to cheating by stealing pitching signs from opposing teams, including the Yankees.

“If these allegations are true, they absolutely should be punished,” add the mayor, who was born in New York but raised in Cambridge, Ma.

Hizzoner, an avid baseball fan, has taken in a number of New York Mets games at Citi Field in Queens, but has yet to venture into the Bronx home of his rival Yankees.

His opponent in the Democratic primary, former City Council member Sal Albanese, was much more blunt when asked for his opinion on the cheating scandal.

“I hate the Red Sox,” he said.