SANTA CLARA, Calif. -- Here is a look at what the San Francisco 49ers must do and can't do Sunday at the New Orleans Saints:Must happen: Get back on track offensively. The Saints are going to score their share of points. They always do. But the 49ers are going to have put pressure on New Orleans by bouncing back offensively. During a five-game win streak -- one that ended Sunday at home against Carolina -- the 49ers scored at least 31 points in every game.