Suffolk Deputy County Executive Jason Elan’s just-announced departure to become communications director for Tom Suozzi’s gubernatorial campaign came with a little present from Elan’s old boss.

At a going-away party last week, Steve Bellone gave Elan a copy of the classic conflict text, Sun Tzu’s "The Art of War."

"You are a fighter in a business that is all about winning," Bellone wrote in part in a note with the book, according to Elan. "For us, winning has always been a means to an end."

The fight was apparent already by Tuesday afternoon, by which time Elan had quickly revved up the Twitter engine to criticize his new boss’ opponent, incumbent Gov. Kathy Hochul.

Elan was once Hochul’s press secretary, part of a career in New York political communications that also included working for Gov. Andrew M. Cuomo and the Independent Democratic Conference before landing with Bellone.

Why leave a job that theoretically could have lasted through Bellone being term-limited in 2023?

"Tom has a real path to winning," Elan told The Point, staying on message.

The Glen Cove Democratic congressman appears to have some ground to cover before June, with Hochul announcing a big lead in campaign fundraising. A new Siena poll of registered Democrats’ primary preferences also shows Hochul with support from 46% of registered Democrats, with Suozzi nabbing only 6%.

Elan explained away the survey numbers by saying that the question was asked of registered Democrats, not likely Democratic voters. He suggested "Suozzi only has room to go up" and Hochul has "capped out" in her support.

One expects it’s this kind of pugnacity Elan will bring from Sun Tzu to Suozzi.

"Battle tested and fiercely competitive, Jason has never been afraid to shy away from a fight worth winning," Suozzi said in a statement.