Sidelined by a fractured left collarbone, Rodgers could only watch in green warmups while Wallace ran through drills Wednesday at practice.
The process of getting Rodgers' presumed replacement up to speed for the Green Bay Packers' game Sunday against the Philadelphia Eagles has begun in earnest.
"You're still learning," Wallace said. "You're never going to get comfortable. Aaron, he's learning each and every day, when we come out here, even though he's been here a long time, there's always something new."
But it sure helps being able to practice with the first-team offense, instead of being relegated to just running through a handful of plays a week.
"Everybody will be much better off," coach Mike McCarthy said. "Not only just Seneca being comfortable going through the reps, but everybody else being comfortable with Seneca."
Wallace is considered a mobile quarterback. He has been around the NFL since 2003, when he was drafted in the fourth round by the Seattle Seahawks. He has played in 63 games, starting 21, and McCarthy doesn't think recognizing defenses will be an issue.
It's more about the coaching staff fitting the game plan around Wallace's skill set, then the backup trying to be the next Rodgers, the 2011 NFL MVP.
"You just have to try to adapt. Like I said, it is up-tempo, fast pace, and try to emulate some of the things he does," Wallace said. "Obviously, it's not all going to be the same, but just try to make sure the receivers and everybody (are) on the same page."
After Rodgers was injured early against Chicago, Wallace was largely ineffective in a 27-20 loss, finishing 11 for 19 for 114 yards and an interception in his first regular-season action since Jan. 1, 2012, when he started for Cleveland in a 13-9 loss to Pittsburgh. For his career, Wallace has a 59 percent completion rate with 31 touchdowns and 19 interceptions.
He'll join a small club. The Packers have had just three starters over the last 22 years — Brett Favre (253 games), Rodgers (86) and Matt Flynn (two).
"It's going to be a good challenge. Obviously, when you lose someone of that caliber, no matter where it is," receiver Jordy Nelson said. "But a quarterback is a little more important. We're all confident in Seneca."
Rodgers has his back. He was officially listed Wednesday on the practice report as having not participated. Coaches don't have to officially rule out players until Friday for a Sunday game.
There was Rodgers at the indoor practice facility, hands on knees a few yards behind the quarterback coach, watching Wallace and newly called up backup Scott Tolzien take practice snaps during light drills. At one point, Rodgers dropped back on his own without the ball and ran through the motions. Facing Tolzien from about 10 yards away, he leaned over with emphasis while watching a pass sail by, as if trying to will the ball to a certain spot.
"Aaron's going about it just as if he were playing in the game," McCarthy said. "He's going right through it right next to Seneca."
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