Nolan McLean (26) reacts after ending the fifth inning at Citi Field, Sunday, March 29, 2026. Corey Sipkin for the NY POST The Mets continue their long road trip out West with a tilt in Arizona against the Diamondbacks, and you can get in on the action with  Fanatics Sportsbook   promo code NYPOST  to unlock this exclusive offer from the sportsbook:  bet $20 and get $200 bonus bets instantly . The first six weeks of the season have been a disaster for the Mets, but they’re saying all the right things about there being a lot of runway left to get back into the mix. We’ll see if they can start stringing some victories together in the Southwest. Fanatics Sportsbook promo code NYPOST for Mets vs. Diamondbacks The Fanatics Sportsbook with promo code NYPOST  can  get $200 in bonus bets instantly  after placing your first $20 bet on anything, including the MLB, NBA, PGA Tour, or Stanley Cup Playoffs.…