Martinez will earn $1 million, with the chance for an additional $500,000 in incentives if the slugger makes the MLB roster. In the minors, he'll get $225,000, according to Mark Feinsand of MLB.com.
The 32-year-old spent the 2020 season with the Tampa Bay Rays and Chicago Cubs, hitting .182/.265/.295 with two homers over 34 games.
The Rays acquired Martinez last offseason as part of the Matthew Liberatore trade, which brought back Randy Arozarena. After posting a roughly league-average .717 OPS in 24 games while acting as the Rays' designated hitter, Tampa Bay traded Martinez to the Cubs. He then went 0-for-21 in Chicago with one walk and seven strikeouts over the balance of the season.
At-bats will be difficult for Martinez to earn with the Mets, particularly if the National League doesn't use the DH in 2021. With Pete Alonso as the everyday first baseman and Dom Smith, Michael Conforto, Brandon Nimmo, and potentially J.D. Davis factoring into a crowded outfield, Martinez's playing time could be limited. Smith, Conforto, and Nimmo are all left-handed hitters, while Martinez is a righty.