A swing flaw ruined the Red Sox' J.D. Martinez in 2020. Here's how

J.D. Martinez, Boston Red Sox DH: 'Chip on my shoulder' is back entering 2021; 'I wasn't really prepared for last year'

Dodgers' J.D. Martinez's swing is must-see viewing for him – Orange County Register

Back at the All-Star Game, Red Sox slugger J.D. Martinez says he's fulfilling his contract to the end - The Boston Globe

jd martinez – Blogging the Red Sox

J.D. Martinez Gives Fascinating Insight On How He's Fixing His Swing

J.D. Martinez has changed his swing and approach - Bless You Boys

Boston Red Sox 2021 Season Review: J.D. Martinez bounces back - Over the Monster

J.D. Martinez on his hitting mentality

How J.D. Martinez transformed an awkward swing into an elite one - The Boston Globe

Red Sox star Martinez focuses on routine to recapture swing