BOSTON -- As the Red Sox head into an offseason of uncertainty, it is fair to wonder if it’s realistic to expect star players Mookie Betts and J.D. Martinez to both return in 2020.

“There’s a way that it could happen, but it will be difficult,” Red Sox president/CEO Sam Kennedy said of having both players on the roster next season.

Here is why.

Owner John Henry is on record as saying he’d like to get the team’s payroll below the first luxury-tax threshold of $208 million for 2020. The Sox had a payroll of roughly $240 million in ’19 (the highest in MLB for the second straight season) while finishing a disappointing 84-78.

It is ultimately up to Martinez if he’d like to return. He holds an opt-out that he can exercise within five days after the World Series that would make him a free agent.

As for Betts, 2020 will be his walk year, and he’s stated numerous times he expects to ride it out until free agency rather than sign an extension with the Red Sox before then. That type of uncertainty could compel the club to trade their best all-around player rather than lose him in exchange for draft compensation.

“Obviously it will be difficult given the nature of the agreements and the contracts that we have in place,” Kennedy said about the possibility of bringing both lineup cornerstones back. “So, look, we have a very targeted and strategic plan that we’re building right now. Some of the dates related to contract decisions come right after the World Series, so we’ve had some time in September to focus on the offseason given where we were in the standings.”

Adding to the uncertainty regarding Betts and Martinez is that the Red Sox haven’t named a successor for president of baseball operations Dave Dombrowski. Kennedy said the search is underway for Dombrowski's successor, noting that the process is in the early stages.

“So, it is going to be a challenging offseason, but we’re ready to tackle it head-on and do everything we can to put a competitive team out there not just for next year but for 2021 and 2022,” said Kennedy.

It is particularly jarring for Red Sox fans to envision a Boston team without Betts next season. He has essentially been the face of the franchise since David Ortiz retired following the ’16 season and is probably one of the top five all-around players in the game.

Betts has been property of the Red Sox since he was taken as a skinny infielder without much power in the fifth round of the 2011 Draft. He is now an elite right fielder who can dominate the game in every way offensively.

“It’s been amazing,” Betts said Sunday of his run with the Red Sox. “I can’t thank the fans and teammates and front office enough for everything. I’m still here. It’s not like I’m gone until whatever. I’m not going to focus on that now.”

After agreeing with the club on a one-year, $20 million contract last season, Betts is due for another bump in his final year of arbitration eligibility.

Once he becomes a free agent, the 26-year-old Betts could look to the contracts signed by Bryce Harper (13 years, $330 million with the Phillies) and Manny Machado (10 years, $300 million with the Padres) last offseason as a starting point for a long-term deal. The 10-year, $360 million extension Mike Trout received from the Angels in March, bringing his total deal to 12 years, $426.5 million over 2019-30, may also be used as a model.

Martinez has three years and $62.5 million remaining on his deal, and he would receive a $2.5 million buyout if he opts out this offseason. Martinez also can opt out a year from now, but he wouldn't receive a buyout.

Opting out would carry some level of risk for the 32-year-old, given how the free-agent market has played out in recent years for veteran sluggers in their 30s.

But Martinez also has to consider the fact that the final two years of his deal could turn into mutual options if he spends a certain amount of time on the injured list with a Lisfranc injury or another right foot ailment, per the terms of the deal he signed in the 2017-18 offseason. In his first two seasons with the Red Sox, Martinez has dealt with occasional back spasms, but hasn’t dealt with any issues with his feet.

Like Betts, Martinez sometimes spoke in a reflective tone during his media availability after the regular-season finale, but he isn’t ruling out a return to Boston.

“It's been great,” said Martinez. “Came and won a World Series. That was the goal. It's been awesome.”

The Red Sox will now wait for the offseason to evolve, acknowledging they’ll have to get more creative to be championship-caliber with a payroll that is all but certain to decrease.

“Yeah, I mean it’s a challenge. It’s a challenge every year,” said Red Sox assistant general manager Brian O’Halloran. “There are 29 other teams that are trying to win a championship as well. The two players you mentioned are incredible players that we hope are on the 2020 team and beyond.

“But there are always challenges with building a championship team, which we aspire to do every year, and doing that efficiently, so we’ll be as creative as we possibly can in finding ways to do that, as John and [chairman] Tom [Werner] and Sam have noted, it’s a goal [to get the payroll below the luxury-tax threshold], not a mandate. So, in an ideal world, it would be great to reset at some point and there are reasons Sam went into for that.

“But ultimately, our goal is to build a championship-caliber team and we’ll do whatever we have to do to do that.”