Per ESPN's Buster Olney, the Red Sox's current proposal to Martinez is "in the range of five years, $100 million."
Bob Nightengale of USA Today previously reported on Jan. 2 that Martinez had a five-year offer on the table from Boston, and the Red Sox "aren’t about to start bidding against themselves" for the 30-year-old.
Back in November, per ESPN.com's Jerry Crasnick, Martinez's agent Scott Boras was seeking a deal around $200 million.
This offseason has been a slow burn, with many top-tier free agents like Martinez, Eric Hosmer, Lorenzo Cain, Yu Darvish and Jake Arrieta still available, which could turn into a buyer's market for teams to get better bargains than they were anticipating three months ago.
The Red Sox need to upgrade the power in their lineup after finishing 26th with a .407 slugging percentage and 27th with 168 home runs last season.
Martinez is coming off a career year for the Detroit Tigers and Arizona Diamondbacks in 2017. He hit .303/.376/.690 with 45 home runs and 104 RBI in 119 games, and his .936 OPS since 2014 ranks seventh in MLB, per Fangraphs.