NEW YORK -- Officially, Zack Wheeler is gone from Flushing. The question is: How realistic it is to think he might return?

Wheeler on Thursday rejected the Mets’ one-year, $17.8 million qualifying offer, a source said, committing himself to exploring free agency for the first time in his career. New York, which will continue its attempt to re-sign Wheeler, is now at least guaranteed a compensatory Draft pick should he land elsewhere.

“We’ll continue to have dialogue with Zack,” general manager Brodie Van Wagenen said before departing the GM Meetings in Arizona. “He’s been a key contributor to our team in recent years. We’ve expressed that. We’ll continue to have dialogue with him, and we’ll continue to do the same with other players.”

The qualifying-offer system, which has been in place since 2012, gives teams the chance to retain free agents at one-year deals worth an average of Major League Baseball’s 125 highest salaries the previous season. Teams tend only to extend qualifying offers to players seeking big multiyear contracts on the open market, resulting in the overwhelming majority of such players rejecting those offers.

Wheeler is no different, coming off a year in which he made 31 starts with a 3.96 ERA and 195 strikeouts in a career-high 195 1/3 innings. Consistent and healthy the past two seasons after missing all of 2015-16 due to Tommy John surgery and complications, Wheeler is arguably the third-best free-agent starter behind Gerrit Cole and Stephen Strasburg.

Per qualifying-cool,offer rules, if a player rejects the offer and signs elsewhere, the club he departed will receive Draft-pick compensation, while the club that signs him will forfeit a Draft pick -- and in some cases, multiple picks. The value of those picks varies based on whether the club receives (or pays into) revenue sharing, and whether the player’s new contract exceeds $50 million. In the Mets’ case, they would receive a pick between the second and third rounds.

Those who reject a qualifying offer, like Wheeler, remain free to negotiate a new deal with their original team for one or multiple years.

“We like Zack,” Van Wagenen said. “In a perfect storm, he would accept the qualifying offer and/or allow us a chance to extend him. But I think good players hit the market. You exercise the rights that you have to try to get the Draft pick.”

The Mets have two advantages in their quest to re-sign Wheeler. One is his familiarity with the franchise, which acquired him for Carlos Beltrán -- now the Mets’ manager -- in a 2011 trade with the Giants. The other is the fact that they are the only team that can sign him without forfeiting a Draft pick.

But the Mets have a disadvantage in that their 2020 payroll is less than $20 million from hitting Major League Baseball’s luxury-tax threshold. Re-signing Wheeler would mean committing a significant portion of their remaining dollars, unless the club becomes willing to pay the luxury tax -- something it has not publicly committed to doing.

In other words, it may be difficult for the Mets to re-sign Wheeler without shedding payroll elsewhere in a trade.

Also working against the Mets is the fact that, like in most years, teams around baseball are clamoring for pitching. The Braves, Yankees and Angels are just three of several teams that figure to check in on Wheeler, who will turn 30 next May.

If the Mets don’t re-sign Wheeler, they will need to figure out how to fill his rotation spot. The team is committed to bringing back Jacob deGrom, Noah Syndergaard, Steven Matz and Marcus Stroman, leaving an open job for either an offseason acquisition or an in-house candidate. Van Wagenen has talked about having relievers Seth Lugo and Robert Gsellman compete for that gig, but doing so would leave New York's bullpen on shaky ground.

Free-agent starters closer to the Mets’ price range include Cole Hamels, Michael Pineda, Tanner Roark and many others, most of them coming with more significant question marks than Wheeler.