SAN DIEGO: Right-hander James Shields, who helped Kansas City reach the World Series last season, has agreed to a four-year contract with the San Diego Padres.

Shields is the latest addition by first-year general manager A.J. Preller, who in December added sluggers Matt Kemp, Justin Upton and Wil Myers, as well as Derek Norris and Will Middlebrooks.

Shields was traded from Tampa Bay to Kansas City two years ago in a deal in which Myers, then the Royals’ top prospect, was acquired by the Rays.

Shields was 14-8 with a 3.21 ERA last season and declined a $15.3 million qualifying offer from the Royals. He lost both of his World Series starts, outdueled each time by Madison Bumgarner.

Meantime, Mark Prior and Moises Alou, forever linked by the Steve Bartman incident that helped deny the Chicago Cubs a trip to the 2003 World Series, have been reunited as roving minor league instructors with the San Diego Padres.

Alou will be a special assistant for player development and Prior will be pitching instructor.

Prior was five outs from pitching the Cubs into the World Series when Bartman touched a foul ball near him in the stands, preventing Alou, the left fielder, from catching it. The Cubs went on to lose the NL championship series to the Florida Marlins, who then beat the New York Yankees in the World Series.