The Miami Marlins and the San Francisco Giants, who meet Monday night to start a three-game series, have vastly different objectives this season. The Giants (33-32) are trying to win now, and they have remained competitive in the National League West, where no team has pulled very far above .500. On Sunday, the Giants posted an impressive victory, shutting out host Washington 2-0, holding the Nationals to three hits (none for right fielder Bryce Harper).