Alex Rodriguez will join ESPN's "Sunday Night Baseball" broadcast team, replacing Aaron Boone, who left to become manager of the Yankees, a source tells MLB.com's Mark Feinsand.The Sporting News was first to report Rodriguez's hiring. A-Rod will join Jessica Mendoza, Buster Olney and a new play-by-play announcer who reportedly will be MLB Network's Matt Vasgersian, replacing Dan Shulman. Rodriguez will continue to work as an analyst for Fox Sports as well.MLB.com