ATLANTA -- Outwardly, the Mets continue to insist that they’re in postseason contention, despite mounting evidence to the contrary -- most prominently, a gap in the NL East standings that’s widening almost daily. Mere days ago, general manager Brodie Van Wagenen said he’s not “looking at anything as a lost season,” citing the Mets’ “talent” and “heart” as reasons to believe things will change.

Yet things haven’t changed -- at least not for the better. The Mets lost three of four to the Cardinals last weekend, then dropped a 12-3 game Monday to the division-leading Braves. The latest loss put the Mets a season-high 8.5 games back in the NL East, trailing a half-dozen teams in the Wild Card race.

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Even Van Wagenen admitted that if this trend continues, the Mets might have to face reality. Most practically, that means trading Zack Wheeler, who allowed five runs (four earned) in six innings in the loss.

“It’s something that you don’t want to think about, but I guess it’s in the back of your head,” Wheeler said. “But I’m here now. I want to help this team win. I know we’re very capable of it.”

Although Wheeler has not been as sharp as last season, he has still typically performed better than he did Monday at SunTrust Park, a few miles from his childhood home. Wheeler allowed a leadoff homer to Ronald Acuna Jr., then another run on a Jeff McNeil misplay in left and a Pete Alonso fielding error. After the Mets tied things on Wheeler’s RBI single in the fifth, he coughed up a Nick Markakis two-run single and an Ozzie Albies RBI hit in the bottom of that inning.

By the time Jeurys Familia and Drew Gagnon melted down for four more runs in the seventh, the Mets were well on their way to their fourth loss in five games.

“We just stunk,” manager Mickey Callaway said. “Again, we weren’t good. We’ve got to recalibrate what we’re doing and we have to do the job better. That’s just plain and simple.”

After Monday’s loss, Callaway focused mostly on the Mets’ bullpen, which fell to 28th in the Majors with a 5.47 ERA. It’s an issue that has cost the Mets night after night, with ramifications throughout the roster.

If nothing else, the Mets’ struggles should result in weeks’ worth of rumors regarding Wheeler, the most prominent impending free agent on New York’s roster. On the surface, Wheeler’s season statistics -- a 5-5 record and 4.94 ERA -- are not overly impressive. A deeper dive reveals a Fielding Independent Pitching mark that’s more than a run lower than his ERA, suggesting Wheeler has been unlucky on balls in play -- case in point Monday, when McNeil misplayed a Josh Donaldson liner into a single, and the Braves hit several other balls just out of reach of Mets defenders.

Wheeler is also healthy, with some of the best pure stuff -- he’s hit triple-digits on his four-seam fastball, and averaged 97 mph on that pitch -- in the Majors. Starting every five games for the Mets, Wheeler is one of 10 Major Leaguers with at least 90 innings and more than a strikeout per frame. The others -- Max Scherzer, Justin Verlander et al -- are mostly a mix of perennial Cy Young Award contenders.

Should the Mets decide to sell, then, a market exists for Wheeler -- just as it did in 2015, when the Mets agreed in principle to a deal to send him to the Brewers, and again last summer, when Wheeler’s name emerged constantly in rumors. This time around, the Mets have little remaining leverage. While rumors should also swirl around Noah Syndergaard, Dominic Smith, Todd Frazier and others, Wheeler is their most obvious chip. If they don’t trade him to a pitching-hungry team like the Yankees or Phillies, they will likely lose him to free agency, perhaps after extending him a qualifying offer and receiving a draft pick in return.

Dealing Wheeler has the potential to net the Mets much more, but would decimate any last-ditch designs they have on competing. It’s an uncomfortable truth that each mounting loss is forcing them to consider.

“We know that we have to win,” Wheeler said. “We have to start winning some ball games pretty soon. It’s to that point in the season where you’ve got to win games. It starts with the pitching. It starts with me.”