Say goodbye to KeySpan Park.

The Brooklyn Cyclones and National Grid, which took over KeySpan Energy Corp., are sliding out of the Coney Island ballyard’s 9-year-old naming-rights deal.

“The fact [is] the KeySpan name no longer exists,” said National Grid VP John Caroselli.

The Cyclones, a Met minor-league affiliate, say they hope to have a new deal and a new name for the park soon.