GREEN BAY – The Packers’ 2015 draft class could play the biggest role it has on defense all season Sunday afternoon in Oakland.

With cornerback Sam Shields missing his second straight day of practice Thursday due to a concussion, the Packers could line up with rookies Damarious Randall and Quinten Rollins – their first- and second-round draft picks last spring – as the primary outside corners against the Raiders. That’s how the Packers’ defense played the second half of last week’s Cowboys game after Shields departed.

Throw in fourth-round selection Jake Ryan at inside linebacker, where he has taken over the starting job in recent weeks, and that’s a ton of defensive youth trying to help usher the Packers back into the playoffs.

Fast friends during the pre-draft process, Randall and Rollins certainly held their own while playing together more than they had previously, albeit against a backup QB for Dallas in Matt Cassel. Veterans Casey Hayward and Micah Hyde are playing plenty as well, with Dom Capers mixing and matching within the nickel and dime packages regularly.

Relying on rookies with so much at stake isn’t perceived as risky, though, at least not with these guys. On Thursday, Head Coach Mike McCarthy complimented Randall and Rollins on the way they practice and study, and how it’s translating to the field. Their teammates show no lack of faith in them.

“They don’t worry me one bit,” Hyde said. “Our whole team has a ton of confidence in them to go out and make plays, and they’re doing just that.”

Randall got off to a fast start this season, earning a defensive game ball for his performance in Week 1 at Chicago, and his game has steadily grown from there. His fourth-down batted pass vs. San Diego followed by interceptions in back-to-back weeks at Denver and Carolina cemented his status as the top rookie on the club.

Rollins has come along more slowly, making a big splash in Week 5 vs. St. Louis with two interceptions, including a pick-six, but not seeing extensive playing time until more recently. His six passes defensed are tied for third on the team with Hayward, behind Randall (14) and Shields (13).

Their rookie seasons haven’t been without rough moments, though. Randall was attacked frequently in those games against the Broncos and Panthers, but bouncing back with the late picks showed a lot of character and ability. Rollins had a missed tackle in the Dallas game that ruptured into a 22-yard gain by running back Robert Turbin, but he shook it off and didn’t compound the mistake.

“I still want to work on my patience at the line of scrimmage,” said Rollins, who played just one season of college football at Miami (Ohio) after a four-year basketball career. “Just being patient with my eyes, my body, putting myself in position to make a play. You want to play fast but you also want to be disciplined.

“For the most part, I’m making progress, which is always good, especially this part of the season, but I’m never satisfied.”

That’s the right approach, particularly when the season is past the point that their performances can qualify as “good, for a rookie.” That won’t cut it against the Oakland receiving duo of Michael Crabtree and Amari Cooper, a rookie in his own right but the top pass-catching one in the league with nearly 1,000 yards.

“No, they make it known pretty much after the bye you’re not really a rookie anymore,” said Hyde, who played a ton of snaps as a slot corner in 2013, his first season. “You know the ropes, you know what to do, so you can’t go out there and make those rookie mistakes. They’re not rookies anymore, and they’re definitely not playing like it.”

Crabtree and Cooper, for the most part, are Oakland’s passing game. They’ve accounted for 43 percent of the Raiders’ receptions (132 of 306) and 49 percent of the yards (1,699 of 3,455) with 11 receiving TDs between them.

Comparing this week to last, Raiders QB Derek Carr poses a far more serious threat than Cassel as well. Combine that with being on the road, and the challenge is obviously larger for the secondary as a whole.

If the group is without Shields, the rookies will be ready. They have no choice, especially at this time of year.

“I’ve never even looked at anything as being a rookie,” Randall said. “I’m out there covering veterans week in and week out, out there in cover zero (with no safety help).

“Everything else is out the window and we’re just ready to get in playoff mode.”

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