Could 2019 be Mookie Betts' final year in a Red Sox uniform? It's becoming increasingly possible, with multiple rival executives telling MLB.com's Jon Paul Morosi that they expect the Red Sox to listen to offers for the '18 American League MVP this offseason.

Betts will be one year away from free agency at the end of the current season, and he rejected an eight-year, $200 million contract extension after the 2017 campaign, per a previous report from MLB Network insider Joel Sherman.

According to FanGraphs, Betts has recorded more Wins Above Replacement (32.9) than any other position player besides Mike Trout since 2015, Betts' first full Major League season. Considering his production and age, the 26-year-old could look to the deals signed by Bryce Harper (13 years, $330 million with the Phillies) and Manny Machado (10 years, $300 million with the Padres) this past offseason as a starting point for a long-term contract. The 10-year, $360 million extension 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.

Besides avoiding the risk of seeing Betts walk away in the 2020-21 offseason for nothing except a potential compensatory Draft pick, the Red Sox could look to trade him as a way to improve their rotation without making a major expenditure, Morosi noted in an appearance on FS1 on Thursday night.

Boston was one of two teams to pay the Competitive Balance Tax in 2018, and the club has the game's highest payroll this season. The Sox already have a substantial amount of money invested in Chris Sale ($145 million guaranteed over 2020-24, with $50 million of that total deferred), David Price ($96 million guaranteed over '20-22) and Nathan Eovaldi ($51 million guaranteed over '20-22), and they will need to replace impending free agent Rick Porcello if he isn't re-signed in the offseason.

Of course, just because the Red Sox might be open to discussing trades for Betts with other teams doesn't mean the superstar outfielder is likely to be dealt. Per Morosi, the expectation of other execs is that the price tag would be steep. How steep? Morosi mentions the Braves as a potential suitor, given their strong farm system and the proximity of Atlanta to Betts' hometown of Nashville, Tenn. But Morosi speculates that it would take a package like outfielder Cristian Pache (Atlanta's No. 1 prospect, MLB's No. 11 overall) and right-hander Ian Anderson (Atlanta's No. 3 prospect, MLB's No. 34 overall) to even get the Red Sox to consider a trade.

Another potential factor is J.D. Martinez's status. The slugger can opt out of the remaining three years and $62.5 million on his contract this offseason, and the Red Sox might be less inclined to trade Betts if Martinez departs.