By Jennifer Piacenti Best bets for three games from Thursday’s MLB Opening Day schedule, including an upset in the Padres-Diamondbacks matchup. Opening Day is here, and it’s time to get in on the action! The season kicks off Thursday at 2:20 p.m. ET when the Brewers head to Wrigley Field to face the Cubs. Seven games will be played, while the Yankees-Red Sox and Mariners-Twins matchups have already been postponed to Friday due to weather. The day concludes with the Padres traveling to face the Diamondbacks. So grab some Cracker Jacks and sit back for a full day of America’s pastime. Now, let’s…