PITTSBURGH >> During Saturday's pregame session with reporters, Dodgers manager Dave Roberts defended slumping first baseman Adrian Gonzalez, saying "I'm not too concerned with him on the offensive side."On Sunday, he benched him for the second half of this four-game series."Just to give him a mental blow, a day away," Roberts said of leaving Gonzalez out of the starting lineup against a right-hander Sunday (rookie Chad Kuhl) and a left-hander Monday (Francisco Liriano).