GREEN BAY – Crouching at the 30-yard line, rocking his weight a little from right to left, Dezman Moses waited to take off on a five-yard head start as Mason Crosby kicked off to start the 2012 season.

Before the Green Bay Packers fell to the San Francisco 49ers 30-22, Moses had sprinted out of the tunnel onto the pristine turf of Lambeau Field for warm ups and introductions, a training camp surprise after being signed as an undrafted free agent out of Tulane.

He stood on the sideline, took in all the green and gold, and listened to the national anthem before over 70,000 fans and a flyover drowned out the final notes.

It was a moment he anticipated since being told he made the team, a moment even his veteran teammates had difficulty articulating.

"It was pretty much what I expected," he said of a feeling he knew even on Wednesday he wouldn't be able to describe. "You get back into that game mentality and you're just trying to really punish people if they're not on your team. It's a defensive mode you go into, and then into attack mode.

"The excitement was nice when I first ran out there and looked around but once the game started it was time to go to work."

Starting on kickoff coverage, Moses began his NFL career by angling down the middle of the field before engaging in a violent collision with the 49ers' Will Tukuafu at the 15-yard line.

The kick resulted in a touch back, but Moses made sure he made the first statement of the day.

"Whenever I play a game I want to be the first to hit someone, to set the tone and set my pads and do all that stuff," he said. "I was definitely looking to hit someone on that first play. Every game I want to start with a big hit, you know, knock the jitters out and let you know you're in the game."

Moses appeared on punt and kick coverage units, and while on the sidelines he shadowed linebackers coach Kevin Greene, waiting for his number to be called on defense.

During the week, he said the biggest adjustment from just trying to make the team to being a member of it was mental sharpness, being focused on his assignments and knowing the 49ers offensive formations.

That was put to the test in the first half with a couple of plays, and then again in the third quarter when Greene signaled him to line up on a 3rd-and-8 play from the 49ers 18. Moses bull rushed on the snap, engaging Pro Bowl left tackle Joe Staley one-on-one. The play went away from him, however – a quick completion of 20 yards, a key play on a 49ers scoring drive.

"You study and try to find your niche or where you can take advantage of a certain player and once you get out there, your instinct kind of takes over and your study kicks in," Moses said of going up against the 6-foot, 5-inch, 315-pound Staley. "Unfortunately it was a three step drop so the ball was out pretty quickly."

Moses had several other opportunities in rush situations, but never managed to get to 49ers quarterback Alex Smith – but he did block for Randall Cobb's 75-yard punt return touchdown in the fourth quarter.

"You're definitely a part of it because we're a team out there," Moses said of Cobb's return. "It's a unit and he's just as important as we are and we take it personal when he's back there. We want to see everyone succeed and especially a guy like Randall, who works so hard and is a special player. You don't want to be that guy who didn't do their job."

The loss dulled the luster of the day slightly for Moses, who had his parents and sister in the crowd, and with another game Thursday against the Chicago Bears it has to be forgotten rather quickly.

His play will be critiqued in the film room, and he'll be expected to get better in a matter of days, but he doesn't need any extra time for the magnitude of being an NFL player to sink in.

"I feel like I'm here now," he said. "It's a hard job and a lot of the work is done in the week of practice. The week of practice is extremely hard and you get after it so we can be prepared for Sundays. The games are the exciting part. That's the fun part. That's like the day off. You can go out there and play in front of 70,000. Your adrenaline kicks in and you've having a good time. Practice where you really have to work for everything that you get. Sundays, for me, is a dream come true."

He laughed.

"I would do that for free."