Harrell gets his shot tonight at San Diego

GREEN BAY (AP) - Aaron Rodgers was ready. So was Matt Flynn.

Perhaps those two wise wagers will earn Green Bay Packers general manager Ted Thompson and coach Mike McCarthy the benefit of the doubt when it comes to giving untested Graham Harrell a shot as Rodgers' primary backup this season.

Harrell figures to get plenty of playing time in the Packers' preseason opener at San Diego on Thursday night, another step for the former Texas Tech star to prove he's up to the task.

And while he'd love to air it out, Harrell knows his first job is showing he can manage the huddle.

"At times, it's going to be different guys and young guys and guys that have never been in, and I think one of the most important things is just to make sure everyone's on the same page and we all know what we're doing and we're all going in the same direction and we all know what we're running," Harrell said. "That gives us a chance to be successful. So I think communication is going to be big for us. As long as we're all on the same page, I think we have a chance to be successful, because we have a lot of talented players."

Harrell knows running the offense smoothly will test his development as a leader.

"That's one of the quarterback's main jobs ... to make sure everyone knows what they're doing. ... If someone's wrong, if we're all wrong together, we still have a chance, you know?" Harrell said. "So that's going to be the key, I think, just being all on the same page and giving ourselves a chance."

Harrell threw 134 touchdowns at Texas Tech, a major college record that stood until Houston's Case Keenum surpassed it last year.

But Harrell went undrafted out of college and got tryouts with the Cleveland Browns in 2009 and 2010, along with a year with the CFL's Saskatchewan Roughriders - although he spent the entire season on the injured list.

Harrell then signed with the Packers in May 2010, was cut at the end of training camp and started the season on the practice squad before being signed to the active roster. Harrell also started the 2011 season on the practice squad before being signed to the active roster. He was active for the Packers' regular-season finale against Detroit, but has yet to take an NFL snap outside of preseason play.

That's likely to change this year.

Flynn turned his handful of impressive outings for the Packers into a free-agent contract with the Seattle Seahawks - although he now finds himself locked in a training camp battle with former Wisconsin quarterback Russell Wilson, a third-round draft pick by the Seahawks.

The Packers (No. 1 in the AP Pro32) didn't sign a veteran backup in the offseason, an indication that they think Harrell can take Flynn's place.

"He carries himself like a quarterback, and he acts like a quarterback," Thompson said. "And I think he thinks he's a quarterback. And he was pretty good in college. So far, he's doing well."

But, as was the case with Flynn - and Rodgers, or any other quarterback for that matter - Thompson acknowledged that they won't know for sure until Harrell actually plays.

"You never know until you know," Thompson said. "Until they go in the game and they actually have to play and make the calls and carry the team and conduct themselves and do all the things that's called for from that position, you never know. But we like what we see."

And Thompson has confidence in the ability of McCarthy and his staff to develop young quarterbacks.

"I personally think our coaches can develop quarterbacks and tweak things if they need to be tweaked," Thompson said. "Sometimes, it's a fine line between being a pretty good quarterback and maybe not good enough. I think our guys have done a good job of working with Graham and getting him farther along."

Harrell spent the offseason working to shore up one of the biggest questions about his game, his arm strength. Now, he says, it's just a matter of getting more experience.

"I think experience is the best way to improve," Harrell said. "I have more experience than I ever have before because I've been here longer. The longer I'm here, the better I feel in the offense."

NOTES: The Packers signed G/T Reggie Wells, claimed WR Andy Brewer off waivers from Philadelphia, placed G Jaymes Brooks on reserve/physically unable to perform and placed T Mike McCabe on injured reserve. Wells has played 117 games in nine seasons with Arizona, Philadelphia and Carolina.