No longer feeling as important to the Packers after two seasons shortened by injuries, Jennings crossed the border and found a team that welcomed him with desperately open arms.
Jennings signed a five-year contract with the Vikings on Friday, leaving Aaron Rodgers and that high-octane passing offense in Green Bay for the unproven Christian Ponder and the ground-and-pound Vikings.
The contract has a maximum value of $47.5 mlllion, with $18 million guaranteed. The contract is worth a minimum of $27 million over the first three years, and could be as much as $28.5 million over the first three years if he goes to the Pro Bowl, according to ESPN's Josina Anderson.
The 29-year-old Jennings played in only eight games for the Packers in 2012, plus two in the playoffs, because of a torn lower abdominal muscle and finished with a career-low 366 yards receiving with an average of 10.2 yards per catch, also his worst NFL total.
In 2011, he missed three games with a sprained left knee. He said he felt lost in the shuffle behind younger Packers receivers such as James Jones, Jordy Nelson and Randall Cobb and sounded determined to prove that his best years are not behind him.
"I can definitely still do it," said Jennings, who will turn 30 on Sept. 21. "I can definitely still make plays and be as exciting as I was in my earlier years."
Then he caught himself and chuckled.
"I am not old," he said. "I am 29 years old!"
If this story of a high-profile Packers player joining the Vikings sounds familiar, that's because it is. Safety Darren Sharper, kicker Ryan Longwell and, of course, quarterback Brett Favre defected before him.
"I'm not the first Packers player to jump on this side," he said with a smile.
Like the others, Jennings will be counted on to fill a gaping hole in Minnesota. The Vikings were in dire need of a No. 1 receiver after trading Percy Harvin to Seattle last week. Even when Harvin was in purple, Ponder had yet to play with a true game-breaker on the outside.
"You can just get a sense that he needed a little more around him to give him some help," Jennings said. "Hopefully, I can help him a little bit."
Looking to give his young quarterback as much help as possible to truly evaluate his ability to be a building block for the franchise into the future, Vikings general manager Rick Spielman went against his philosophy of spending big money on outside free agents to get Jennings locked up.
"I'm a very strong believer in building through the draft," Spielman said. "But every once in a while something unique will come about that you just want to make sure that you can get accomplished to get that player here."
The two-time Pro Bowl pick will immediately be the leader of a nondescript receivers group that includes Jerome Simpson, who is coming off an injury-plagued 2012 season, and second-year slot receiver Jarius Wright. Jennings will be counted on not only to help Ponder but the teammates at his position, including any rookies they draft next month.
The transition from a former league MVP in Rodgers to the still-developing Ponder won't be easy. Jennings spoke highly of his time in Green Bay, where he was drafted in the second round in 2006 and spent seven years catching passes from Favre and Rodgers.
He spoke honestly about the hesitation of playing with a quarterback who has been wildly inconsistent in his first two years in the league. So he sat down and watched some video of the Vikings from last season.
"I had to watch Christian," Jennings said. "I had to see what I was [getting] myself into. Very athletic quarterback, obviously his upside, his future is bright. I saw a young guy that was maturing."
What Jennings does have now that he never did in Green Bay, however, is an All-Pro running back. A league MVP, in fact. Adrian Peterson finished last season 9 yards short of breaking Eric Dickerson's single-season rushing record.
Jennings has admired Peterson from the other side for years, never more so than in 2012 when he watched Peterson come back from a torn ACL in his left knee to carry the Vikings offense into the playoffs last season.
"You see a guy like 'All Day' sitting in that backfield and you see the cluster of guys that are gathered in that box for him, it's going to be some special things taking place," Jennings said, smiling again.
Widely praised as a respected locker-room presence who relished charitable work in the Green Bay community, Jennings certainly will be a breath of fresh air in Minnesota off the field as well.
One of the main reasons the Vikings parted with Harvin was the trouble the volatile 24-year-old would occasionally cause behind the scenes. That probably won't be an issue with Jennings.
"He's as great player," Ponder said of Jennings earlier this week. "He's been doing great things in Green Bay, and he'd bring leadership to that position. Kind of a dynamic guy you can put in the slot and outside. I've always admired his work in Green Bay, and he seems like a great guy to have on a team."
Said coach Leslie Frazier: "We're really excited about the fact that he brings high character. He's a tremendous athlete. We all know that. But what he'll bring to our locker room, the energy that he'll bring to what we do at practice along with his leadership, those were all qualities we were looking for when we talked with Greg."
Jennings dined with Frazier, Spielman, offensive coordinator Bill Musgrave and defensive end Jared Allen at a downtown steakhouse on Thursday night before the two sides got down to business on Friday.
Jennings said he and his wife quickly felt as if they were part of a family. The Vikings were the only team he visited, and he said he had an inkling on his way to Minnesota that this would be where he ended up.
"I definitely wanted to know that they wanted me," he said. "I wanted to feel that they wanted me to be a part of what they were doing and a part of the future. And I got that feeling early and I got that feeling quite often."
Information from The Associated Press and ESPN's Josina Anderson was used in this report.