By Dan Lyons The Mets first baseman had two hits in the Opening Day win, but took a big hit as well late in the game. Thursday night’s Opening Day win at the rival Nationals wasn’t all celebration for the Mets. Late in the game, Pete Alonso hit the deck after being beaned by Nats pitcher Mason Thompson. A mid-90s fastball from Thompson sailed on him, striking Alonso in the shoulder. The pitch ricocheted and hit the slugger in the faceguard, leaving him with a bruised and bloodied lip. Alonso immediately hit the ground, making for a frightening scene for the Mets and their fans. Luckily, he is …