Sidney Rice arrived in Minnesota five months before his 21st birthday. He was a “Great Dane,” coach Brad Childress recalled, a gangly and loping receiver whose limbs were “all over everywhere.” In fact, what stood out more than anything in Rice’s first minicamp was neither his speed nor his receiving ability. It was his arm.

Yes, Rice gunned the ball during pre-practice warm-ups -- so much so that the Vikings incorporated a reverse pass for him in their playbook. They used it twice, both for completions, during the 2007 season. As a receiver, however, Rice showed only glimpses of why he was a second-round draft choice that year. He made a few acrobatic red zone catches, but a slow recovery from a knee injury left him with 46 receptions over his first two NFL seasons.

Those circumstances have made Rice’s emergence this season all the more amazing. A receiver once noted more for his arm, and then seemingly pegged as a red zone specialist, will be one of the most-feared offensive players in Sunday’s NFC Championship Game. Rice punctuated an 83-catch regular-season performance with a historic playoff debut last Sunday against Dallas, putting his name among the most explosive receivers in the history of the NFL’s postseason.

How did it happen? Let’s recount the ways:

Knee issues

In September 2008, Rice suffered one of the most frustrating knee injuries a receiver can have: a sprained posterior cruciate ligament. There is no surgery to speed recovery, and typically it’s not serious enough to require extended time off.

So Rice limped through much of the year and, as it turned out, the offseason as well. It wasn’t until July 15, 2009 -- 10 months after the injury -- that Rice began running without a knee brace. Rice chronicled the day in a moving entry in his personal blog, one that describes a workout with Arizona receiver Larry Fitzgerald and former Vikings receiver Cris Carter, now an ESPN analyst:

“I turned over a new leaf today. What a great day.

First of all, I worked out full speed without my knee brace for the first time in 10 months and felt no pain.

Second it was one of the toughest workouts I ever had. …

I partnered with Larry Fitzgerald through the whole workout and he stayed on me all day making sure I was doing everything right. Near the end we did acceleration drills and then we did four 300-yard shuttles. It was by far my hardest complete workout of the offseason.

I didn’t think I would make it through the whole thing. But I was running alongside Larry and he just kept talking to me, motivating me the whole way. After the second 300 I was hurting real bad, and when it came time for the third he said we had to make a better time than the last one. After that one I couldn’t feel my legs. I went down to the ground, gassed, and he was like, get up. He made me walk with him for active recovery, they call it.

I was going just on spirit after that. For the fourth one Cris jumped in next to me. I thought my legs were about to fall off but he pushed me through it and I was able to finish.”

When he reported to training camp, Rice was a different player. He was faster, in far better condition and armed with a number of new body-positioning techniques gleaned from Fitzgerald and Carter -- two of the NFL’s more physical receivers in recent years.

Connection with Favre

After earning a starting job in training camp, Rice suddenly found himself working with a new quarterback. Brett Favre signed with the Vikings on Aug. 18, less than a month before the start of the regular season.

Put simply, Rice and Favre bonded instantly. It didn’t take Favre long to see that Rice, still only 23, possessed the instincts of a veteran packed into a 6-foot-4 frame.

“What he lacks in speed,” Favre said, “he makes up for in his physical [skills] and really his knowledge. You either have football savvy or you don’t. I’m a firm believer in that. You can take the fastest guy, and it’s happened in the NFL, you can take a track guy and try to make him a receiver. Yeah, he can fly. But can he adjust to the ball? Can they catch a back shoulder [pass]? Can they go up at the high point of a ball? Can they leverage a corner? Those are things you can’t coach.”

Favre began sitting in on receiver meetings to watch film, and literally has never stopped talking with Rice since he arrived.

“People ask how we built a relationship so well through his short time here,” Rice said. “It’s all communication. I’ll be sitting at home, and if he sees something [on film] he’ll send me a text to let me know. We’ll come in the next day and just watch whatever he was talking about.”

Trust factor

The Vikings were one of two teams in NFL history to have six players make 40 or more receptions this season, a testament to the balanced nature of their offense. Still, Rice was Favre’s most-favored receiver; he targeted Rice on 119 passes this season, often into what appeared to be solid coverage.

Rice rarely found himself wide open this season. Separation is not his strength, but Favre quickly learned to trust him to beat defenders to the ball.

“Some of the passes he throws to us as receivers, not all quarterbacks would throw them,” Rice said. “He has a trust in us that really helps us out.”

Consider his first touchdown against the Cowboys last Sunday. Dallas approached him with a Cover 2 scheme that left safety Gerald Sensabaugh in single coverage down the right sideline.

“I consider that a mismatch every time I see it,” Favre said.

When you watch the replay, you see Sensabaugh running stride for stride with Rice. You can also see Rice use the trick of a veteran receiver: He kept his hands out of sight until the last possible moment. His eyes on Rice, Sensabaugh had no idea the ball was coming. He turned back at the same time Rice made the catch, leaving him out of position to make a play.

I’m sure the Saints have studied that play and Rice’s other two scores as well. The question is: What can they do about it? Double-teaming Rice is something few opponents have tried this season, knowing it will leave another proven receiver -- Percy Harvin and Bernard Berrian, or tight end Visanthe Shiancoe -- in a favorable mismatch.

As a result, Rice has caught at least two passes in every game this year and has at least six receptions in eight of his past 11. Despite his speed limitations, he ranked fourth in the NFL with seven receptions of 40 yards or more.

If the Vikings win Sunday, it’s hard to imagine Rice not playing a central role. Great Dane, indeed.