BOSTON -- In about six weeks, Marcus Stroman will become a free agent for the first time in his career. By the end of the offseason, his value will be clear in dollars and cents.

Until that time comes, debates will rage about what kind of deal Stroman can receive on the open market -- and whether it might be the type of contract the Mets will be willing to offer. In taking the loss in a 6-3 defeat to the Red Sox at Fenway Park on Tuesday, Stroman made both his attractive qualities and his limitations plain to see.

Sharp early, Stroman caved for three runs during the game-winning rally in the fifth -- one on a Kiké Hernández leadoff homer, then two more on a Xander Bogaerts go-ahead shot. The home runs increased Stroman’s ERA to 3.00, which ranks in the top 10 in the Majors among qualified pitchers. However, that mark comes over 174 innings for Stroman, who has averaged only 5 1/3 innings per start.

While that may be typical for many starters in today’s game, it could nonetheless give teams pause if they are looking to pay Stroman like a top-of-the-rotation starter. So could the fact that he is ending the season on a relative downturn, with a 3.77 ERA since the start of August.

“I didn’t make pitches when I needed to,” Stroman said of Tuesday’s defeat.

The Mets could not save Stroman in this one, mustering their only offense against Red Sox starter Eduardo Rodriguez during a two-run rally in the fourth. When third-base coach Gary DiSarcina sent Pete Alonso home on a Michael Conforto single, Hernández threw him out with ease, stunting what might have become a bigger inning. Alonso later hit his 34th homer, though by the time the game ended, even he -- the most optimistic of Mets -- acknowledged that making the playoffs is “unlikely.”

While that may be true, for those like Stroman who can enter the market this offseason, there is still plenty left to play for. Stroman’s skill set is not the prototypical one to command a nine-figure megadeal in a sport that values power more than anything else. For years, Stroman has relied on movement more than velocity, which has allowed him to remain successful despite striking out less than a batter per inning -- an almost unheard of statistic for a player who, in Jacob deGrom’s absence, has served as New York’s staff ace throughout the second half.

But Stroman’s success is hardly due to batted-ball luck; he has consistently rated near the league leaders in ground-ball rate throughout his career, relying on devilish sinkers, sliders and split-changeups to elicit weak contact.

“He can induce contact. He can throw strikes,” Mets manager Luis Rojas said. “He’s got a good repertoire. If something’s not working, he can choose one pitch and probably use it a little more than the other and be effective. … Stro’s been consistent for us. Especially without Jake.”

Stroman will also benefit from a weak starting-pitching market. He will enter free agency alongside names like Kevin Gausman, Robbie Ray, Max Scherzer and Carlos Rodón, all of whom carry question marks of their own. Surely, every name on that list will generate interest from pitching-starved teams.

Which brings Stroman’s current club back into the picture. Entering the offseason, the Mets feature as many pitching quandaries as any team. Noah Syndergaard can become a free agent. deGrom and David Peterson will be coming off injuries. Tylor Megill and Taijuan Walker could be dealing with the effects of significant innings spikes this summer. Few, if any, prospects will be ready to contribute in meaningful ways. As such, the Mets will almost certainly be in the market for pitching, with an eye toward solidifying the middle of their rotation.

Stroman fits the profile, if the Mets believe in his long-term consistency.

“I take the same mentality into each and every game,” Stroman said. “Regardless if my team scores any runs or not, I’m trying to do my best to limit their team and go as deep as I can into the game. So that mentality is very consistent. I feel like that’s been able to put me at a point where I can consider myself a workhorse, and someone who goes out there and throws 170, 180, 190, 200 innings every year, and someone who can take the ball every fifth day and give my team a chance to win.”