NEW YORK -- Although the Mets’ offense has ranked among the game’s best since the second half of the season began, Michael Conforto has not joined the party. Arguably the Mets’ most-feared hitter heading into a contract year, Conforto has been unable to roll his success from the pandemic-shortened 2020 season into 2021.

Conforto’s hitless performance was hardly unique in the Mets’ 2-0 loss to the Braves in Game 1 of a doubleheader Monday at Citi Field. But it was part of a larger trend for the outfielder, whose 1-for-19 stretch has dragged his average down to .201. Conforto stranded three men on base in the seven-inning game, including two when he struck out to end a 10-pitch at-bat against Braves starter Kyle Muller in the third.

That was the Mets’ best threat against Muller, who held them scoreless over five innings. New York starter Marcus Stroman was less effective, giving up eight hits and two runs in five innings of his own, but he kept the Mets within striking distance. They simply never struck.

“Today, I don’t think he took his ‘A’ swing,” Mets manager Luis Rojas said of Conforto.

From a personal perspective, this has always been an important season for Conforto, who can become a free agent at season’s end at age 28. Entering the year, Conforto was the clear head of a free-agent outfield class that may also include Nick Castellanos, Kyle Schwarber, Mark Canha, Starling Marte and Tommy Pham. Many around the industry expected George Springer’s six-year, $150 million contract with the Blue Jays to represent the floor of what Conforto might be able to expect.

But while many of his classmates are enjoying fine seasons, Conforto is not. His batting average, slugging percentage and league-adjusted OPS+ are all career lows by significant margins, sitting far beneath the career-best rate stats he posted over 54 games in 2020. Conforto missed more than five weeks earlier this season due to a right hamstring strain, and he’s been less productive since returning than he was over the first month-plus of the season.

It’s a problem for Conforto, who might have to consider accepting a qualifying offer this offseason to reestablish his value if he continues to slump. But more pertinently, it’s a problem for the Mets, who need Conforto to be a pillar of their offense. Even as Pete Alonso, Jeff McNeil and others have emerged from early-season slumps, Conforto has not.

He and Alonso had the best chances to crack Muller in Game 1 of Monday’s doubleheader, coming up with two men on base and one out in the third. But after Alonso struck out, Conforto fouled off five consecutive pitches before whiffing on a slider below the zone.

“I thought his timing was just a tap off there in that game,” Rojas said. “He’s not getting ready on time. His hands are too rushed forward, and there’s not a lot behind the swing. But he’s made the adjustment game to game.”