10″ x 8″ Grand Slam vs. New York Yankees (during 2018 regular season)photograph, signed in silver marker by Boston Red Sox star J.D. Martinez, who added his number “28” after his signature.

Signed at an official paid private autograph session.
Sold with Certificates of Authenticity from both the Autograph Source (Lifetime Guarantee) and independent third-party authenticator Beckett Authentication Services.