A.J. Ewing left a strong impression on Mets officials during spring training, and his fast start this season has already earned him a promotion.

The club announced Monday that Ewing was moved to Triple-A Syracuse.

The 21-year-old outfielder produced a .349/.481/.571 slash line in 18 games for Double-A Binghamton this season.

MLB Pipeline ranks Ewing the No. 3 Mets prospect and No. 85 in all of baseball.

“There’s a lot to like,’’ manager Carlos Mendoza said in March. “I like him as a hitter at the plate. And his defense, he gets great jumps and made some good plays with reads off the bat.”

Ewing projects as a center fielder, a potential need for the Mets in the near future.

He also stole 70 bases last season.

“His ability to give you a really good at-bat from the left side and speed is pretty encouraging,’’ Mendoza said.

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The Mets are still deciding on the next step for Kodai Senga, according to a club source, following his ugly performance against the Rockies.

It was a third straight rough outing for Senga.

Senga could be asked to accept a minor league assignment — a move the Mets utilized last year when the right-hander finished the season at Triple-A Syracuse — or slide him to the bullpen.

But the Mets already have two other displaced starters (David Peterson and Sean Manaea) in the bullpen, complicating the equation.

Senga has a 6.94 ERA over his past 14 starts, dating to July 11.

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Austin Slater, who was signed by the Mets on Sunday — Tommy Pham was designated for assignment — will be active for Tuesday’s game, the team announced.

Slater, who brings a right-handed bat, had a .470 OPS in 12 games this season with the Marlins before his release.

The Mets also claimed infielder Eric Wagaman from the Twins and optioned him to Syracuse.

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The Mets’ 9-19 record is tied for the second-worst start over 28 games in franchise history.

Only the 1981 Mets (who started 8-19-1) were worse.

The 1962, ’64 and ’83 Mets all started 9-19.