GREEN BAY, Wis. -- The last thing you'll ever hear Scott Tolzien say is that he has mastered the Green Bay Packers offense and what it takes to play quarterback in it.

"It's always a work in progress," Tolzien said.

But considering where he was less than two years ago, when he was the second of three quarterbacks who tried to fill in for Aaron Rodgers after he broke his collarbone during the 2013 season, Tolzien should be in a much better position to keep the Packers afloat should anything happen to Rodgers again this season.

"I think Scott's made great strides," Packers coach Mike McCarthy said of backup quarterback Scott Tolzien. Jeff Hanisch/USA TODAY Sports

"I do feel more comfortable because you've been here and you're more familiar with the playbook, the coaches and the guys around you, but there's still so much to learn, especially when you watch Aaron," Tolzien said after a recent organized team activity. "He's at such a different depth in the offense."

So is Tolzien compared to where he was on Nov. 10, 2013, when he was thrown in against the Philadelphia Eagles after Rodgers' first replacement, Seneca Wallace, pulled his groin. Tolzien had been promoted to the active roster that week, just two months after he arrived in Green Bay as a practice-squad player. He played parts of three games, including a pair of starts, but managed just one touchdown pass and five interceptions while completing 61.1 percent of his passes before coach Mike McCarthy decided it was Matt Flynn's turn.

Still, McCarthy saw enough potential in Tolzien that he wanted to work with him again. The Packers kept three quarterbacks on their opening-day roster last season -- Rodgers, Flynn as the No. 3 and Tolzien -- for the first time since 2008. Tolzien did not take a single snap last season and was active for only three games (including playoffs) as the No. 3 quarterback after Rodgers strained his left calf in Week 16.

Now, Flynn is gone, and it's Tolzien's turn.

These days, the ball flies out of Tolzien's hand more quickly, and he hits receivers in stride more often. It's a product of two full offseasons and a productive preseason last year in which he actually outplayed Flynn.

In last week's open OTA practice, Tolzien had a 65-yard drive to lead the No. 2 offense to a win in the two-minute period. Tolzien calmly fired an 8-yard touchdown pass to tight end Richard Rodgers with 1 second left.

"I think Scott's made great strides," McCarthy said after that practice. "Scott is definitely one of the quarterbacks that I've seen over the years make big changes to his throwing motion, his fundamentals. You can see his footwork is intact and now he's been able to tie all of that to his knowledge and understanding of the offense and getting timing with the players that he's been here with in the past and creating it now with the young players."

Tolzien wouldn't get into specifics about what he worked on with McCarthy, associate head coach Tom Clements and quarterbacks coach Alex Van Pelt. The catch-all phrase was "fundamentals," but it's clear they were designed to improve Tolzien's delivery.

"You're always trying to get a rhythm with the routes and then just things with ball carriage, weight distribution, a lot of different things," Tolzien said. "It gets complex, but it does make a difference."

At this point, there's little reason to think Tolzien won't be Rodgers' No. 2 this season. Even the addition of fifth-round pick Brett Hundley, the ex-UCLA quarterback, shouldn't change that this season. The Packers likely will keep three quarterbacks again.

Another sign of what the Packers think of Tolzien is this: After making the league minimum of $645,00 last year, the one-year deal he signed on March 9 could be worth up to $1.35 million if he's on the 46-man game-day roster each week.

"It's a world difference,” Tolzien said when asked to compare where he's at now with when he first arrived in Green Bay. “Even just having game action, that helps tremendously. But I think there's so many layers to the offense that back then I was trying to learn the '101' version and now I'm trying to learn a little bit more in depth. But you've got to work in it each day."