Mario Manningham practice 49ers

The 49ers have been starved for receivers all season. So when Mario Manningham started practicing, it was treated like a national holiday. Even though Manningham’s best game as a 49er wasn’t all that great — a five-catch, 73-yard performance in a 26-3 loss last year to the Giants —  the fact that he wasn’t Kyle Williams, Jon Baldwin or Kassim Osgood was enough. Couldn’t be worse, right?

Manningham hasn’t been worse. But with only four receptions for 38 yards in his first two games, he hasn’t been much better, either.

Manningham was on the field for 45 of 57 possible snaps against the Panthers. He was targeted six times, catching three passes and dropping two others. Manningham (knee) was limited in practice last week and listed as “Questionable” heading into New Orleans, where he only played 27 snaps out of 59. Colin Kaepernick targeted Manningham three times, with Manningham catching one pass for eight yards to convert on 3rd-and-8.

Jonathan Baldwin got 16 snaps, catching no passes on three targets. The 49ers went with two running backs, two tight ends and one wide receiver fairly often against New Orleans, a personnel grouping Greg Cosell described yesterday as something one might see in the 1960s.

Manningham could get things going against Washington on Monday night, since their pass defense is among the worst in the league. And the 49ers could get a boost when Michael Crabtree comes back, either at Washington or a week later against St. Louis. That’s the optimistic way of looking at things. Manningham may be nothing more than a borderline No. 3 receiver for the rest of the season, even if the pain in his knee subsides.

Crabtree hasn’t practiced in full yet, at least as far as anyone outside the organization can tell. He probably isn’t anywhere close to what he was last season from a conditioning standpoint, so it’s far from a given that Crabtree’s return will automatically jumpstart the team’s stagnant passing game. Banking on guys returning from injury isn’t the best plan in the short-term, and these were major injuries. Manningham’s knee injury in Seattle was almost as gross as Jabari Greer’s on Sunday (poor guy), and there was nothing partial about the way Crabtree tore his Achilles.

If the 49ers make it to the playoffs, both receivers might be close to 100% by that time. Like 85%, for instance. Maybe even 87%. When Crabtree returns, the attention he’ll receive will provide openings for other, healthier players. His presence will also allow the 49ers to bring their personnel groupings back into the 1990s, at the very least. That’ll probably have to be enough until Crabtree gets into game shape. As the 49ers fight to stay in the playoff picture, it will be up to Kaepernick and the coaching staff to integrate Manningham and Crabtree into the offense slower than some may have hoped. Depending on either receiver to spur an immediate offensive transformation will lead to the 49ers staying home in January for the first time in three years.