GREEN BAY, Wis. -- After the Green Bay Packers’ defensive debacle in their season-opening loss, first-year defensive coordinator Joe Barry put on a good face.

“You never have to worry about me,” Barry said days after the 38-3 loss to the New Orleans Saints. “Promise.”

"Never" might be next week.

If the San Francisco 49ers continue what the Saints did in Week 1, and what the Detroit Lions did in the first half of Week 2, then worry might set in -- if not from the exuberant Barry, then from those around the Packers who wonder if their defense can turn things around.

In the first six quarters of the season, the Packers looked discombobulated on defense. Miscommunications, wide-open receivers and little or no pass rush. Then they shut out the Lions in the second half of Monday night’s game to help turn a three-point deficit into a 35-17 win that kept the Packers from their first 0-2 start since 2006.

“I think back to my past experiences, whether it’s being on new staffs or with the offense,” Packers coach Matt LaFleur said. “For example, look how far we came from ’19 to ’20.”

Two games does not an evaluation make, especially when they’re the first two games of a coordinator’s tenure. But a slow transition was a risk the Packers knew they were taking when they decided to change defensive leadership.

Or perhaps it wasn’t their choice.

After last season, the Packers announced Mike Pettine “will not return” as defensive coordinator, but it might have been as much Pettine’s call. He had come to the end of his contract, and after what happened in the NFC Championship Game, and more importantly how it was handled afterward, there’s reason to believe Pettine did not want to return.

After that game, LaFleur left Pettine open to criticism when he said the coverage on Scotty Miller’s 39-yard touchdown with one second left in the first half was “definitely not the right call” and called it “inexcusable.” Although LaFleur said he blamed “us coaches for putting our guys in that situation,” many interpreted that as blaming Pettine. It wasn’t until after Pettine’s departure that LaFleur called it “a flat-out miscommunication” between him and Pettine and said, “anytime something like that occurs, that 100% falls squarely on my shoulders."

Which brings things to Barry and communication. LaFleur had a conversation on the sideline with Barry just before halftime on Monday night after the Packers' defense failed to come up with a stop that would have allowed Aaron Rodgers and the offense to get a possession to end the first half. Green Bay would receive the ball to start the second half -- the so-called “double up.”

LaFleur said he talked to Barry about either playing coverage or bringing pressure.

“Because when we were doing our four-man rushes and playing man coverages behind it, we weren’t getting to the quarterback,” LaFleur said.

Barry understood.

“I was irate because we have a damn good quarterback here and the whole theory, most people’s theories are when you have the luxury of being able to start with the ball to start the second half, what you want to do is you want to get your offense and your great quarterback the ball to end the half and then to start the half, right?” Barry said. “That’s why a lot of people defer. That’s the whole reason why they do it.

“Of course, I was furious. ... We settled down and held them to a long field goal, but still we didn’t get the ball back for our offense. I was upset. Matt was upset, too. He has every right to be as the head coach.”

Sure enough, the Packers' pressure numbers spiked in the third quarter. According to ESPN Stats & Information research, Barry blitzed on all five of the Lions’ dropbacks in the third quarter. Overall, the Packers' blitz percentage was 41% against the Lions compared to 16.7% in the opener against the Saints.

“He’s the head coach; he has every right to suggest, demand, whatever,” Barry said. “By no means is Matt that way. He’s very collaborative.”

Forget statistics after two weeks; there’s not even enough data to call it a trend. For example, the Packers' sack total (one on an unforced fumble by Jared Goff) and their sack percentage (1.6 per dropback) rank last in the NFL, but their standing in the ESPN pass rush win rate (39.6%) of 21st isn’t disastrous.

Barry made some changes from Week 1 to Week 2, most notably getting first-round pick Eric Stokes on the field more. He played 44 snaps against the Lions after eight against the Saints. Barry created a spot for Stokes by moving cornerback Kevin King to the nickel or slot position.

Although there was a miscommunication on the Lions’ first touchdown, Stokes brought an energy to the defense that showed when he almost knocked out some of outside linebackers coach Mike Smith’s teeth with a celebratory head-butt after a fourth-down stop in the fourth quarter.

“This is a step in the right direction,” said linebacker De'Vondre Campbell after his 13-tackle, one-interception performance against the Lions.

Sunday night’s game should reveal whether it was as Campbell described or just one step up and two steps back.

The 49ers do more to try to confuse defenses than anyone in the league. While the Packers should be familiar with it because LaFleur came from that system and runs a similar scheme, 49ers coach Kyle Shanahan takes it to extremes. Since 2019, the 49ers rank first in most plays involving motion before or at the snap, fifth in play-action plays and second in both. The Packers rank 11th, seventh and sixth, respectively, according to ESPN Stats & Information research.

This season, the 49ers lead the NFL in using motion either at or before the snap on 84% of their offensive plays, according to research by ESPN Stats & Information. Second in the league are the Kansas City Chiefs at 65%. That’s a potential landmine for a defense still finding its way.

Barry should know what to expect considering he spent the past four years coaching in the same division as the 49ers while linebackers coach for the Los Angeles Rams, who also run a version of the Shanahan offense.

The growing pains the Packers might have to live through on defense this year -- as LaFleur noted by comparing them to the improvements the offense made from Year 1 to Year 2 under his watch -- might impact how Rodgers and the offense play. Or at least how they strategize.

Without a defense that can be counted on to come up with a stop before Rodgers & Co. take the field, the Packers might be better served to get away from trying the double-up situation that failed against the Lions.

“I was thinking back to 2016 when we went on that run, one thing that changed was we started taking the ball just to get the momentum going early in the game,” Rodgers said. “I’ve always enjoyed the defer -- obviously, you can’t always win the toss -- but defer and the double-up opportunity last drive of the first half and the first half of the second half. But that might be something that we might look at.”