FLOWERY BRANCH — With dreadlocks flowing from under his helmet, Dunta Robinson swaggered around practice Wednesday with that knowing smile, that fearless little nod of the head, the look that lets everyone know: Don’t bother throwing this way. No one can beat me.

The Atlanta Falcons can’t wait for him to show off some of that bravado against another team.

He’ll finally get his chance on Sunday.

Robinson, a lock-down cornerback so desperately needed on a defense that struggled the past two years, was sidelined early in training camp with a strained left hamstring.

Even though he’s been practicing regularly over the past two weeks, the Falcons decided to take no chances with their major free-agent signing.

Robinson sat out all four preseason contests, which means he’ll be thrown right into the fire when the Falcons play the first game that counts against the Pittsburgh Steelers.

He’s not sure how he’ll feel.

“I have to play a game in order to get in game shape,” Robinson said. “I’m not in game shape right now. That won’t happen until I play a football game. That’s what I’m looking forward to Sunday.”

The Falcons are counting on Robinson to beef up a secondary that was burned big time in 2009. Even mixing up the schemes to become less predictable, they still gave up more passing yards than all but four teams.

Enter Robinson, who signed a six-year contract that included about $22.5 million in guaranteed money.

Atlanta is counting on him to provide the sort of defensive presence that was missing in coach Mike Smith’s first two seasons. Robinson will likely spend most of his time trying to jam the opponent’s top receiver at the line before dropping into coverage.

He’s been regarded as one of the league’s top cornerbacks ever since he broke into the league in 2004 with six interceptions as a rookie for the Houston Texans.

Now he’s home, playing for a team he used to cheer for as a kid, the one that practices only about 45 minutes away from where he grew up in Athens.

“I think we have all the tools,” Robinson said. “We have the physical attributes to go out there and dominate football teams. Now we’ve got to believe we can do it.”

Confidence is not a problem for Robinson. Like any great cornerback, he has no doubts about his abilities and a very short memory. He’s had only seven picks over the last five years — none in 2009 — but that was largely because teams didn’t throw his way very often.

The rest of the Atlanta secondary looks forward to having Robinson hold down one side of the field.

“He gives me the ability to free my eyes up,” safety Thomas DeCoud said. “I’ll be able to make plays on the ball and not necessarily have to worry about backing up a corner.”

Receiver Roddy White has gotten to work against Robinson in practice and believes he’ll have a positive impact on the entire defense. That’s a key for the Falcons, who have plenty of offensive weapons with Matt Ryan, Tony Gonzalez and Michael Turner but will likely go only as far as the guys on the other side can carry them.

“They’ve been going a lot of good things,” White said. “I expect them to be one of the top secondaries in the league.”

Robinson will rely on his body to let him know how much time he should be on the field against the Hines Ward and the Steelers.

“I won’t try to do too much,” he said. “I won’t try to do more than I feel my body can do. I’ll just go out there and get a feel of it. If I feel fine, I’ll keep playing. If I feel like I need to take a break in between for a couple of plays, I’ll come off the field.”

While playing his college ball at Georgia, Ward got a chance to watch Robinson play a few high school games and knew he could be something special. Not much has changed.

“Dunta is still a great cornerback,” the Steelers receiver said Wednesday.

Robinson would love to talk a little smack when he lines up against Ward. Their respective schools — the cornerback left home to play for South Carolina — will face each other the day before in a matchup of ranked teams.

“I hope the Gamecocks take care of business,” Robinson said. “I know I’m in Georgia, I know I from Athens. But I went to South Carolina, people. Please don’t throw eggs at my car when I walk out the door.”

Asked for a prediction, Robinson said, “No man, I don’t have a score.”

Then, he quickly added with that cocksure look of his, “Carolina by 21.”

NOTES: Smith confirmed the starting lineup, which was a bit up in the air on the defensive side. Kroy Biermann will start at left end, having beaten out former first-round pick Jamaal Anderson. Trey Lewis will start at tackle in place of Jonathan Babineux, suspended from the opener for an arrest on marijuana charges. Brent Grimes is listed as the starting cornerback opposite Robinson, though he was limited in Wednesday’s practice by an ailing hip. ... WR Michael Jenkins (shoulder) did not participate in practice after missing all four preseason games. He’s still listed as the starter on the depth chart, though he’s at the optimistic end of the recovery period from his injury. If he can’t go, Brian Finneran is expected to start.