GREEN BAY, Wis. – Dom Capers didn't even want to think about where the Green Bay Packers would be without defensive tackle Letroy Guion.

At first, he chuckled at the suggestion, and then he turned serious.

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"I'm just glad he filled a real need for us," the Packers defensive coordinator said this week. "One of the things about this game is you can run out of big guys that can make plays in there pretty quick. It becomes tough sledding if you don't have those guys."

Nine months after the Packers signed him with little or no fanfare, Guion is one of the centerpieces of a much-improved defense that is preparing for the playoffs.

The Packers have more than gotten their money's worth on the one-year, $1 million contract Guion signed on March 18 as a street free agent who had been cast aside by the Minnesota Vikings. The 6-foot-4, 315-pound former fifth-round pick had career-highs in tackles (62) and sacks (3.5) this season.

"Letroy has been everything we thought he was going to be," Packers coach Mike McCarthy said. "I've always had a lot of respect for Letroy in Minnesota. I think he's come over to us, and I think he's taken his game up a notch. He's an excellent fit in the locker room; teammates love him. He's an excellent teammate and he's a damn good football player.”

Now, they’re looking to bring back the 27-year-old for next season and perhaps beyond.

His agent, Seth Katz, said Wednesday that negotiations on a new contract have begun.

"We've had some very, very early conversations," Katz said. "The Packers are obviously focused on the postseason, but we know how they feel about him, and they know he wants to be back. We're not making it a secret that he wants to stay in Green Bay."

When asked this week whether this season was the start of a long-term relationship with the Packers, Guion said: "I sure hope so."

No one knew exactly how Guion would fit in with the Packers or whether he would even make the team. But his importance became clear after B.J. Raji tore his right biceps tendon in the second-to-last preseason game and was lost for the season. At that point, however, Guion had yet to even participate in a training camp practice because of a hamstring injury. He made his practice debut two days after Raji's season-ending injury.

"You were starting to get a little concerned in training camp because we couldn't get him on the field," Capers said. "We had liked what we had seen in OTAs. You could see a big guy that had some quickness and athletic ability, but especially when coming into a new system because there's a lot of little things you kind of have to learn those on the run, but I think that's why you've seen him settle in during the second half of the season."

Guion started all 16 games at the nose tackle position the Packers had carved out for Raji, who returned on a one-year deal that will expire in March.

"I knew I was going to come in here and play some type of role," Guion said. "I didn't know what it was."