GREEN BAY, Wis. – Mike Singletary says his team's No. 1 formula is this: "We go out and we hit people in the mouth."

OK, so how come his 49ers continue to be a punching bag to start games?

Their 30-24 loss to the Packers on Sunday was disappointingly similar to an earlier loss to Houston. In both instances they had plenty of time to rest up and prepare, and in both cases they should have come charging out of their corner like Mike Tyson.

Instead they came out like Michael Spinks.

Afterward, Singletary struck a familiar theme in saying that the 49ers' problems center around their lack of maturity.

"We have to settle down," he said. "Our young guys have to settle down and play football and understand that this is 49ers football going forward."

Singletary, however, needs to start pointing at himself and the rest of the coaching staff. The 49ers had what amounted to a second bye week to get ready for a game with all sorts of NFC playoff implications. It's not that they swung and missed Sunday. It's that they didn't start swinging until they were down.

On offense, the 49ers started out as tentative as a kitten. Alex Smith hardly uncorked a pass beyond 10 yards in a first half in which he had a grand total of five passing yards. The 49ers had nine days to get ready for this game but still seemed paralyzed by Green Bay's ever-changing 3-4 defense.

Offensive coordinator Jimmy Raye admitted during the week that he altered his game plan after watching the Packers beat the Cowboys last Sunday. Smith furthered this sense that the 49ers allowed Green Bay to be the aggressors, that they were psyched out from the get-go.

He said that in the first half, offensive players were looking at each other hoping someone would make a play. He suggested the team had no definitive plan of attack entering the game. He described the 49ers as "a little unsure" as the first half unfolded.

"So you put in a game plan that hopefully takes care of all they can give you," Smith said.

The defense seemed just as insecure, even though Aaron Rodgers had been sacked 41 times entering the game. But the Packers quarterback wasn't sacked in the first half – and, let's be honest, the first half decided the game – and threw for 274 yards, more than he's ever thrown in one half of play.

The 49ers' defensive backs, meanwhile, were intimidated by the Packers receivers' reputation for gaining yards after the catch. Cornerback Tarell Brown, a player who three weeks ago was given a starting nod ahead of Nate Clements and who just signed a contract extension, was routinely 10 yards away from the man he was covering.

The cushion didn't help. Brown was victimized on Greg Jennings' 64-yard catch-and-run touchdown in the second quarter and then whiffed on a tackle when Jordy Nelson scored 6 1/2 minutes later on a seven-yard pass.

"In my mind, we're going to continue to work," Singletary said. "We're going to continue to fight, we're going to continue to do the things that good teams do. Today we did not act like one, we did not play like one."

Strong words. But they weren't delivered with the thunder they were last season when Singletary took over.

Midseason funks have become routine in San Francisco. A year ago, Singletary was able to knock the 49ers out of that annual drive with oration and sheer force of will.

But that combination doesn't seem to be working this season. Moving forward, the 49ers need both emotion and a sound strategy. And on Sunday they had neither.

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