SANTA CLARA. (AP) — Randy Moss still carries himself with that same old swagger and avoids saying much about his NFL return after a year away. Mario Manningham has no qualms speaking out about how he wants to show the West Coast what he can do seven months after leading the New York Giants to a Super Bowl title.

The San Francisco 49ers are depending on this talented twosome for an upgraded receiving corps in 2012. As close as the Niners came to the Super Bowl last season, their wide receivers faltered when it mattered most.

The last time San Francisco played in late January, the wideouts managed one catch for three yards in a 20-17 overtime loss to Manningham and the Giants in the NFC championship.

Now, there are bigger expectations on quarterback Alex Smith to throw deep. He will get his first chance in the season opener Sunday at Green Bay.

"When you add some weapons to the mix like Manningham and Moss, you can open it up more," Packers quarterback Aaron Rodgers said Wednesday. "On paper they look a little better."

Smith realizes the questions about Moss could be an advantage, perhaps providing some mystery or element of surprise. Yet the 35-year-old Moss has had his share of memorable days at Lambeau Field.

It was after his antics in Green Bay during the 2004 playoffs for the Vikings that Moss was fined $10,000. He pretended to pull down his pants and moon the Wisconsin Cheeseheads during Minnesota's playoff win in which he caught two TD passes.

"For sure, the unknown," Smith said of what Moss will offer on game day. "It works both ways, the unknown and what they're going to do. A guy like Randy and the unique toolset that he has creates a lot of problems. I think it gives them a lot to think about — the big-play potential, the matchup problem that he is."

Moss, who last played for New England, Minnesota and Tennessee in 2010, has 13 career regular-season touchdowns against the Packers and 15 total — eight of those at Lambeau.

Moss' best season came for the Patriots in 2007, when he caught 98 passes for 1,493 yards and a single-season record 23 touchdowns in helping New England to a 16-0 regular-season record. He has 954 catches for 14,858 yards and 153 TDs in his 13-year career.

Manningham is even more for the defense to handle. He caught a 17-yard touchdown pass from Eli Manning with 8:34 remaining in regulation of the NFC title game to help New York beat the Niners.

He had five more receptions for 73 yards in the Giants' 21-17 Super Bowl victory over the Patriots, including an over-the-shoulder 38-yard catch between two defenders on which he managed to stay inbounds to start the game-winning, 88-yard touchdown drive.

The 26-year-old Manningham, who had 39 catches for 523 yards and four touchdowns total last year, recently missed some time while attending his grandfather's funeral in Ohio. He said Wednesday he spent eight hours at team headquarters during the off days working to catch up.

"Just trying to do what we have to do to just be explosive, go out there and make plays," he said, referring to himself and Moss. "I can't wait to go out there and play with my new team and show them what I've got."

They should complement tight ends Vernon Davis and Delanie Walker and receiver Michael Crabtree, who had 72 receptions for 874 yards and four touchdowns last season as San Francisco went 13-3 and ended an eight-year playoff drought.

"It definitely gives them a different dimension, no doubt about it," Packers coach Mike McCarthy said. "They've definitely added a lot to their perimeter. Their vertical passing game is improved greatly just getting off the bus. I've always like their tight ends. Vernon and Delanie are excellent players, and now to add that whole group of receivers with them, it's a dynamic perimeter."

Rodgers is eager to see what Smith does this year — just not this Sunday — to follow up a breakout 2011 performance in which he threw only five interceptions. Smith was the No. 1 overall draft pick in 2005 out of Utah, while the Niners passed on Rodgers out of nearby California and he fell to 24th.

The two friends even spent some time together during the offseason in San Diego. And don't refer to Smith as a "game manager" in front of Rodgers, the way some people did last year.

"I think that term is a condescending term for quarterbacks," Rodgers said. "I don't think he's a game manager, I think he's a guy who takes care of the football and makes a lot of plays. I don't think he got the respect that he deserves. I've been friends with him since we were 21 and I've followed his career. It's nice to have been able to reconnect over the last year or so. I definitely pull for him and enjoy watching him play."

Niners coach Jim Harbaugh didn't want to guess how Moss might do in his first game after a year off.

"I don't know if I'd be the best person to give that summation," Harbaugh said. "I wasn't on the same team as Randy any time before this year, but it's been good and we've been very pleased to have Randy on our team."

Notes: Harbaugh was non-committal about the health of RB Brandon Jacobs (left knee) and WR/return man Ted Ginn Jr. (right ankle) and whether they might be ready for Sunday. "Not sure," Harbaugh said. Neither player was in pads or practicing during the open period of an afternoon workout Wednesday. Jacobs was in a brace and Ginn rode the stationary bike. ... When Rodgers was asked about needing two blockers against 49ers standout DT Justin Smith, he noted it could take more. "Maybe three or four, depending on where he lines up," Rodgers said. "I think he's definitely one of the best players in the NFL regardless of position."