GREEN BAY, Wis. — Let the fun — and the thumping — begin.

After they eased into playing football again, Mike McCarthy is looking forward to seeing his Green Bay Packers in pads for the first time since the end of last season.

"When you put the pads on the first time, yeah, it'll definitely be more urgency than it's been down there the last two days," McCarthy said Saturday.

Green Bay's eighth-year coach indicated that the first padded practice of training camp Sunday morning would provide a dose of reality for the team's younger players.

There's also anticipation on what the day will bring for a group of veteran linemen who expect to get their first true test at their new positions.

"Pads tell you a lot," offensive tackle Marshall Newhouse said.

McCarthy made sweeping changes across the offensive line when the Packers held offseason workouts in the spring.

Coming off a season that had franchise quarterback Aaron Rodgers on the ground far too often, the major overhaul included flipping both sides of the line.

Right tackle Bryan Bulaga and Pro Bowl right guard Josh Sitton are now entrusted with protecting Rodgers' blind side.

Sitton said after the Packers' second practice day of camp Saturday there's still work to be done for him and Bulaga to be completely comfortable in their new roles.

"I don't feel 100 percent over there yet. It's going to take time," said Sitton, a starter for the Packers at right guard since his rookie season in 2008. "There's a lot of different things that you have to work on. It's not just being over there for a month and getting a feel for it."

The transition would seemingly come easier for Bulaga, who's back playing his natural position. He started at left tackle his final two years in college at Iowa.

Yet after the Packers made Bulaga their first-round draft pick in 2010, he replaced an injured Mark Tauscher at right tackle a month into that season and continued to start there the last two years.

Bulaga didn't return to left tackle until McCarthy made the bold move of shuffling four of the five starters on the line at the start of organized team activities in May.

"I think just from kind of getting used to the left side again in OTAs was good, and you've got these (first) two days (of camp) without pads to kind of get that muscle memory back from what you were doing in OTAs," Bulaga said. "And then Sunday you get into pads and then you feel a real tempo and whatnot."

Rodgers has been encouraged by what he has seen with the changes on the line, particularly with Bulaga as his new outside protector on the critical left side.

"I feel good about it, I really do," Rodgers said Friday. "I think Bryan is really feeling comfortable at left tackle. Other than center, for me, it's my most important position there. So (Bulaga) needs to feel comfortable, and if he does, then we'll be fine."

How well guard T.J. Lang and tackle Newhouse, the starters on the left side the past two seasons, adjust to playing the right side also will be vital in trying to keep Rodgers out of harm's way.

Rodgers, the NFL MVP in 2011, was sacked a career-high and league-worst 51 times last season.

"I don't think about how many sacks we gave up," Sitton said. (And) I don't think about it as any more pressure (this season). It's all the same. Our job is to keep (Rodgers) upright and to create a hole for the running back. That's always our job. So there's no more added pressure."

Still to be determined in the next month of the preseason is whether Newhouse and young center Evan Dietrich-Smith can hold onto their spots.

Don Barclay has taken first-string reps at both right tackle and center since camp started. Barclay made six starts at right tackle as an undrafted rookie to end last season after Bulaga suffered a season-ending hip injury.

"We think Don Barclay's a heck of a football player, and he's earned the opportunity to compete for starting positions on our football team," McCarthy said. "With Evan there, I feel like he established himself at the end of the year, but we want to make sure we are creating competition."

That's OK with Rodgers, who isn't in a rush to have his restored cast of protectors settled.

"I think it's going to take some time," Rodgers said. "I think the run periods in training camp are going to be very important, to get those guys on the run fits working together, Josh and Bryan working together, T.J. and Marshall working together, seeing how the competition plays out. I think it's going to take a little bit, but by the end of the preseason we have to be ready to go and those guys have to feel comfortable, and I think they will be.