CINCINNATI — The Mets needed a Knicks-like comeback Monday night, but instead of getting Josh Hart, they showed little heart.

In a nothing performance, the Mets were bludgeoned in the first two innings and then went quietly in a 12-0 loss to the Reds at Great American Ball Park.

A shaky pitching rotation was further exposed as Tobias Myers had a brutal start in his return from Triple-A Syracuse, dampening some of the positive vibes from last weekend’s series victory over the dominant Braves.

On a day the Mets lost Christian Scott to the injured list with a right hip impingement, further raising questions about the starting pitching, Myers surrendered seven earned runs over 1 ⅓ innings.

Eugenio Suarez created most of the misery, with two home runs, including a grand slam, in helping the NL Central basement dwellers beat the Mets for a third time in four meetings this season.

Suarez finished with six RBIs.

Only adding to the Mets sense of uncertainty is Kodai Senga’s scheduled return from the injured list to start Tuesday night.

Will the Mets receive a respectable version of the right-hander or will it be the pitcher who cratered in the second half of last season and owned a 9.00 ERA before he was sidelined in April with lumbar spine inflammation?

Offensively, the Mets were punchless against Chase Burns and the Reds bullpen, finishing 1-for-12 with runners in scoring position.

This after scoring seven and eight runs in their two victories over the Braves at Citi Field.

Burns lowered his ERA to 2.01 with five scoreless innings with four hits and three walks allowed and seven strikeouts.

It was an 11th straight start for the right-hander with two earned runs or fewer surrendered.

Myers didn’t need long to get roughed up.

Blake Dunn opened the game for the Reds with a double and stole third as part of a double steal after Sal Stewart’s walk.

Spencer Steer’s ground out gave the Reds their first run.

With two outs, Myers ran the count full to Suarez, who blasted a four-seamer over the left field fence to give the Mets a 3-0 deficit.

But that was hardly in the Mets’ worst inning of the night.

In the second, Myers loaded the bases on a walk, single and mishandled but before walking JJ Bleday with the bases loaded.

Jonathan Pintaro entered and allowed a single to Stewart that extended the Reds’ lead to 5-0, with the bases still loaded.

Suarez unloaded them with his ninth career grand slam, a shot that cleared the center field fence.

Bleday launched a three-run homer in the eighth against David Peterson for the Reds’ final scoring.

Peterson allowed three earned runs on two hits and two walks over three innings — his third straight underwhelming performance from the bullpen.