There will be a fourth member of the Padres major league cast participating in the World Baseball Classic. Padres bench coach Rick Renteria will manage Mexico in the 16-team tournament. Luke Gregerson will be in Team USA’s bullpen. Outfielder Chris Denorfia will play for Italy. And right-hander Edinson Volquez could get the opening-game start for the Dominican Republic when pool play begins in two weeks. “It’s quite an honor for me and my entire family,” said Renteria, who will manage Mexico in the same pool as the United States, Italy and Canada. That pool will play in Phoenix.