GREEN BAY -- Not once. Not twice. Three times, the Green Bay Packers kickoff coverage unit failed to do its job. And that was simply too much for special teams coordinator Mike Stock to bear.

"The bottom line is we had people in the right spots, they have to do the right thing at the right time. You've got to make a tackle," Stock said after watching Carolina Panthers kickoff returner Mark Jones make a major impact on field position and momentum in the Panthers' 35-31 victory Sunday at Lambeau Field.

"When you have to do what we did — keep coming back, keep coming back, keep coming back — and then you give the field position back to the opposing team, it stops the momentum. It swings the other way. No question about it."

How much so?

"I thought the biggest negative today was the field position. That's two weeks in a row that we're playing on a football field that's 200 yards longer than our opponent," Packers coach Mike McCarthy said. "It's tough to overcome that. I thought that was a huge factor. Just look at the statistics."

After the Packers' first points on Mason Crosby's 32-yard field goal, Jones returned the ensuing kickoff 42 yards to set up a Panthers touchdown for a 14-3 lead.

After the Packers took a 28-21 lead on Greg Jennings' 21-yard TD reception, Jones returned the kickoff 51 yards, setting up the tying score.

"(It's) just (little) breakdowns on the kickoff coverage and that's all it takes," Jarrett Bush said. "This is the NFL, players can make plays. ... That's all it takes — small mistakes that barely anyone notices, but that's what happens."

And after Crosby's 19-yarder made it 31-28, the coverage crew failed again, letting Jones get free for 45 yards before the go-ahead TD.

"Two minutes left in the game, it's field position and time to make the big play," McCarthy said. "And we didn't get that done."

Health watch

Aaron Rodgers could tell center Scott Wells (concussion) wasn't quite himself when he sailed a shotgun snap over the quarterback's head, setting up a Panthers touchdown that made it 21-10 at the half.

"I could tell on the previous drive when we went down and scored a touchdown. There was a run to the left and he came back to the huddle - and I know Scottie; I've known him for four years now, he's an extremely tough guy — and it looked like something was a little bit off," Rodgers said of Wells, who did not return after the errant snap.

Without Wells, Jason Spitz moved to center and Josh Sitton came in at right guard.

The Packers also lost halfback Ryan Grant to a sprained right thumb in the second quarter, although he said he expects to play next week against Houston. "I probably could have gone back in, but both sides felt like, with the amount of pain and how swollen it was, ball security-wise it was better not to go in," Grant said.

Safety Atari Bigby, who played sparingly with Charles Woodson moving to his position, left the game with a shoulder injury and did not return. Defensive linemen Jeremy Thompson (ankle) and Kenny Pettway (knee) also did not return. Safety Nick Collins (hip) and returner Will Blackmon (head) returned from their injuries.

Right tackle Mark Tauscher said he felt no ill effects from the hamstring injury he suffered Monday night, and "it was just a case of trusting I'd be all right. I didn't feel like it was limiting me. I felt OK when I was out there."

Clear decision

With his team facing fourth-and-goal from the 1 and the game tied at 28, McCarthy said he did consider going for the touchdown with 1:57 to play. But afterward, McCarthy said he was convinced he made the right decision to have Crosby kick the 19-yarder, even though Carolina came back to take the lead.

"(Going for) it was an option. But to go up three points with 2 minutes left at home, I was confident in that position, so that's why I kicked it," McCarthy said.

Said offensive coordinator Joe Philbin: "Absolutely, you've got to take the lead, I would think. We're (more) disappointed that we had the ball with 1:25 left and didn't do anything with it. That's plenty of time to go win the game. That may be more disappointing."

Frost draws boos

Beleaguered Packers punter Derrick Frost's woes continued. On four punts, he averaged 43.8 gross yards, 32.3 net yards and 3.63 seconds of hang time, and the crowd of 70,297 let him have it when his first boot was a 2.96-second line-drive 40-yarder that netted just 28.

By comparison, Carolina's Jason Baker averaged 46.2 gross yards, 42.3 net yards and 4.1 seconds of hang time. Frost departed without comment, ignoring a reporter who approached him and said his name three times.

"I think it had a bearing in the game early, there's no question about it, as far as field position," Stock said. "He needs to improve, he needs to improve, he needs to improve."

Extra points

Defensive end Aaron Kampman again was the Packers' only pass rush. He had two sacks, giving him 9.5 on the year. The Packers have 20 total. ... With eight catches for 91 yards, Jennings surpassed the 1,000-yard mark for the first time in his career (1,057 yards). … The Navy Parachute Team, scheduled to perform at halftime, was forced to cancel due to windy conditions. … Middleton's Brett Joers (10 and 11 year olds) was among the winners as the Packers played host to the annual Punt, Pass & Kick competition.