MANKATO, Minn. — The Minnesota Vikings have been in training camp for just over a week, giving us a chance to start to get a read on various issues that will impact this team as it attempts to repeat as NFC North champion. With players enjoying their first off day of camp Sunday, here is our analysis of five areas on which we’ve been keeping a close eye.

QUARTERBACK DERBY
Brett Favre’s decision to remain retired meant the Tarvaris Jackson-Sage Rosenfels battle for the starting job was back on. The competition was derailed a bit on the second day of practice when Jackson suffered a Grade 1 (the least serious) sprain of the MCL in his left knee that sidelined him for three days. He and Rosenfels are now back to splitting reps with the first-team offense.
Our take: The fact Jackson has a better understanding of this offense was clear in the opening three practices, but Rosenfels’ comfort level in running this version of the West Coast system appears to be increasing with each practice. Of course, the fact that Rosenfels got all the work he wanted with the first team for three days had to help. Neither Jackson nor Rosenfels appears to have pulled ahead in this race, and that might not happen until the Vikings open the preseason Friday in Indianapolis.
PERCY IMPACT
The Vikings vowed to use rookie Percy Harvin in myriad ways after drafting him in the first round, and so far that has been the case. Harvin missed the first few days of camp while his contract was being finalized, but he has caught on quickly since arriving. He has played multiple receiver spots, lined up in the backfield, taken the direct snap in the Wildcat formation and is returning punts and kickoffs.
Our take: Harvin still has to prove himself in real game action, but he certainly looks like the real deal. He is incredibly fast, knows how to make defenders miss and has good hands as a receiver. If he can stay healthy and the Vikings use him like they are in camp, Harvin could make a huge impact in his first season.
ROOKIE SURPRISE
Like Harvin, the rest of the rookies are unknowns until they show what they can do when the season starts. That said, the first glimpse at the 2009 class is pretty favorable. Phil Loadholt appears to have the right tackle job all but locked up, and Asher Allen and Jasper Brinkley have shown flashes of their talent at different times in the first week of camp.
Our take: Brinkley has made people notice him because of his violent hits. The fifth-round pick from South Carolina is extremely physical and seems to thrive when contact is involved. He is competing for the backup middle linebacker job and should help the special teams units.
A NICKEL FOR YOUR THOUGHTS
The Vikings don’t have any battles for starting positions on defense, but who will serve as the nickel back has not been determined. Among the competitors for the job to serve as a fifth defensive back in passing situations are cornerbacks Benny Sapp, Asher Allen, Marcus McCauley and newcomer Karl Paymah. Sapp was used in this role last season after Charles Gordon was lost for the season in November because of a leg injury.
Our take: Defensive coordinator Leslie Frazier and defensive backs coach Joe Woods have not tipped their hand about who is going to win this job. Sapp’s strongest competition might come from Allen, a third-round pick from Georgia. Allen isn’t afraid to hit and showed some impressive flashes early in practices. McCauley, a third-round pick in 2007, was used in the nickel as a rookie but saw very limited playing time last season. When McCauley is used, he takes over at left cornerback and Antoine Winfield moves inside. Sapp has the ability to play inside. Paymah’s biggest contribution is likely to come on special teams.
THE RECEIVING END
It seems safe to say that Bernard Berrian, Percy Harvin, Sidney Rice and Bobby Wade are going to be on the opening day roster. That means that if the Vikings again keep five wide receivers, there is going to be a healthy competition for that last spot between Jaymar Johnson, Darius Reynaud and Glenn Holt.
Our take: Holt was signed as a free agent from the Bengals during the offseason, but that doesn’t mean he’s a lock to make this team. Johnson, who spent last season on the practice squad, might be the early front-runner. He spent the offseason concentrating on getting stronger, and he also focused on becoming a reliable punt returner. Jobs like this are often won because of ability to contribute on special teams, and the fact that Johnson could win the punt return job might make him the choice. Reynaud and Holt can both return kickoffs, but it’s likely Harvin is going to handle those duties. Johnson also hasn’t hurt himself by making some nice catches.