The Mets went to bat for the families of two slain New York City police officers at the team’s home opener Monday at Citi Field.

A crowd of 43,947 fans stood and cheered when the images of Detectives Rafael Ramos and Wenjian Liu were shown on the scoreboard before the game, a 2-0 Mets victory over Philly.

Liu and Ramos were in a patrol car in Brooklyn last December when they were gunned down at point-blank range by a man who said he was targeting cops as revenge for the deaths of Eric Garner and Michael Brown at the hands of police.

Ramos’ two sons, Justin and Jaden, and their mother, Maritza, joined Liu’s widow, Sanny Chen, and parents to throw out ceremonial first pitches to Mets stars David Wright, Matt Harvey and Curtis Granderson.

Moments earlier, more than 150 NYPD officers unfurled a giant American flag in the outfield as Aviation Unit helicopters did a flyover.

Mayor de Blasio, who joined them on the field, didn’t get as much love from the crowd. He was booed, as he was last year.

The mayor’s relationship with police has been strained in the wake of the Liu and Ramos murders. Cops even turned their backs on him at the funerals.

[theplatform account=”4uMbOC” media=”media/guid/2389494712/9D585E59-5F38-302A-D953-B542F54361EA” player=”0VXqAhlG36_T” params=”feedParams=byCategories=seriesevents”]