Monday was J.D Day for the Boston Red Sox. Slugger J.D. Martinez informed Chief Baseball Officer Chaim Bloom that he will be back with the team for the 2020 season, rather than opting for free agency.

The news is a double-edged sword for Bloom and General Manager Brian O’Halloran. It helps them maintain an offense that has been one of the best in the game over the past two seasons. But it makes it tougher to reach the franchise’s stated goal of lowering payroll next season, when Martinez will make $23.75 million.

Martinez has done everything the Red Sox could have hoped for when they signed him to a five-year, $110 million contract in early 2018. He led all of baseball in RBI over the past two seasons. He hit more opposite-field home runs than anyone in the game. He posted a ridiculous .985 OPS over two seasons, and in 2018 became the first player ever to win two Silver Slugger Awards as the best hitter at two different positions (outfield and designated hitter).

Oh, and he helped lead the Red Sox to a championship.

It’s easy to forget that the contract Martinez signed gave the Red Sox a lot of protection. He had dealt with a foot injury in the two seasons before joining Boston, so the team gave itself an opt-out in Years 3 and 4 of the deal if the injury recurred. It was an insurance policy of sorts, but it came at a price.

Martinez got himself a little protection, too. That’s how he came to control his destiny, with language allowing him to opt out of the contract this fall  – and he has opt-out clauses after the 2020 and 2021 seasons – in search of greener financial pastures. The final two years of the contract (2021 and 2022) drop to $19.35 million per season.

Any team would want a bat like that in the lineup for years to come. Yet the Red Sox aren’t just “any team.” They had the highest payroll in baseball over those two years, and are paying an exorbitant price for it. The Red Sox future is as much about money spent as it is about runs scored. They want to reset their Competitive Balance Tax next season, getting below $207 million – meaning someone’s got to go.

That’s why there’s a very real chance the Red Sox will trade Mookie Betts in the coming months, even though he is undoubtedly one of the game’s best players.

Having Martinez back in 2020 makes it even more difficult to bring Betts back into the fold. With money tied up in the DH, there’s undoubtedly a stronger chance the Red Sox listen to offers for Betts, the Gold Glove-winning superstar. Betts made more than $27 million last season and is arbitration-eligible again this winter.

Last week, Bloom spoke to Red Sox season ticket holders on a conference call I hosted. It didn’t take long for the conversation to turn to Betts.

“I don’t know yet what is going to happen,” said Bloom. “We would certainly love to keep him in our uniform forever if we can. We’re just going to have to see, once we have our arms around all the different options, what is the best thing for us.

“He’s going to have to make that decision for himself, and we’re going to have to decide what the best thing is – taking into account everything and all the trade-offs involved in these types of commitments – what’s the best thing for the long term of the Boston Red Sox.”

That long-term future is now coming into focus. Martinez is staying, and that’s good news for the Red Sox offense. It just might not be good news for Sox fans who want Betts back in the lineup, too.

Tom Caron is a studio host for Red Sox broadcasts on NESN. His column appears in the Portland Press Herald on Tuesdays.