Released after playing in two games with the Miami Dolphins back in Weeks 2-3, Walden eventually landed in Green Bay on Oct. 27 as the Packers were signing reinforcements for an injury-depleted linebacking corps.

Then to everyone’s surprise, even his, he was playing in a game just four days later. Given a package of plays in the third-down nickel defense to learn in his first week with the Packers, Walden was on the field for the opening third down, and a few others later on, against the Jets in Week 8.

His impact in the 9-0 shutout victory was minimal, statistically anyway, but the impact on his psyche was immeasurable.

“That felt tremendous, being out a month and being able to come in and contribute like that to help the team win,” Walden said. “That was big for me as far as my confidence.”

It gave Walden a new lease on his football career, and he now finds himself about to make his first start in three seasons in the NFL on Sunday night in New England. Head Coach Mike McCarthy announced on Friday that Walden would take the starting outside linebacker spot normally manned by rookie Frank Zombo, who is listed as doubtful with a knee injury.

It’s been a familiar refrain for the Packers’s defense this season, seemingly always needing a young, unproven player to step in and take on a greater role. At outside linebacker specifically, the defense already had lost Brady Poppinga and Brad Jones to season-ending injuries before Zombo, a non-drafted rookie, hurt his knee last week in Detroit.

How Walden will fare against the league’s most explosive offense and the planet’s hottest quarterback is anyone’s guess, but the Packers feel he’s as prepared as possible. With Clay Matthews unable to practice during team (11-on-11) periods for the last several weeks due to a shin injury, Walden already had been taking all the practice snaps with the first-team defense.

That kind of work is invaluable, especially for a player who had so much more to learn than the sliver of the playbook he was handed his first week here.

“He’s come light years since then,” outside linebackers coach Kevin Greene said. “Then, he was really limited in his knowledge of our defense, and we were just trying to put him out in specific situations where his job description was very narrow and focused. Now, he’s absorbed an entire defense, and he’s ready to do whatever he needs to do in any and all defenses.”

That’s the challenge Walden faces now – to be a complete player. Thrown out there against the Jets in Week 8 specifically as a pass rusher, Walden obviously was being asked to do what the coaches felt he did best.

But setting the edge against the run and dropping into coverage are also in an outside linebacker’s job description, and the Patriots feature dual threats both out of the backfield (BenJarvus Green-Ellis and Danny Woodhead) and at tight end (Aaron Hernandez and Rob Gronkowski).

Walden, a Middle Tennessee State product, admitted that defensive coordinator Dom Capers’ scheme is more complex than others he’s played in for Kansas City (2008) and Miami (2008-10), so learning it was a process. In that respect, the need for Walden to play right away when he arrived worked to his advantage, because he was able to start the process by focusing on certain packages he absolutely needed to know before expanding his knowledge from there.

Since the Jets game, he has played occasional snaps on defense and regularly on special teams while getting all those reps in practice.

“I think he’s a totally different player right now than he was then because when we brought him in, we didn’t have much chance to teach him much of first and second down,” Capers said. “He was in third down and just had very limited assignments, where now he’ll have the whole package on his shoulders.”

The boost of confidence from getting on the field that first week has played a role, too. Cut four times in his career – by the Cowboys, who drafted him, and the Chiefs in 2008, and by the Dolphins twice this year – Walden said he put his “nose to the ground” in studying the defense, knowing he was viewed immediately by the coaching staff as a potential contributor and not just an extra body for practice.

“He’s a smart kid,” Greene said. “He’s very self-conscious. He wants to do well. He’s not an ego I have to deal with. He wants to learn, he wants to listen, he asks questions. He’s a good kid to have in your (meeting) room. He doesn’t cause any problems. There’s a lot of things I like about him.”

Now it’s up to Walden to show all those things when it counts. Sunday will be his 35th game as a pro but his first start, in prime time and on national television against a Super Bowl favorite, no less.

Walden knows as well as anyone that chances like this don’t come around often, and he said as much during the week. Like every opposing offense the Packers face, far more attention schematically will be paid to Matthews than whoever the outside linebacker is on the other side, so the opportunity to make an impact will inevitably present itself.

“He’s a very explosive player,” Matthews said. “It will be interesting to see him come out there and see what he brings to the table. Obviously we have all the confidence in the world in him. It’s his time.”

He made the leap from the street to third downs in four days. The next step comes Sunday night.

“I believe he is (ready),” Capers said. “I think he’s been working hard and he’s like all these young guys – this is going to be his opportunity, and I think he’s ready to jump out there and take advantage of it.”

Additional coverage - Dec. 17