Since the first game of the season, a cloud has hovered over the Vikings' running game. Adrian Peterson's legal troubles whipped it up into a storm and without former backup Toby Gerhart to step in, dark clouds increased on the horizon. But rookie Jerick McKinnon has begun to emerge from the squall and could be the Vikings' future at the position.

McKinnon's performance last week against the Buffalo Bills was mildly surprising on a couple of fronts. Since he gave McKinnon the starting role over Matt Asiata two games ago against the Detroit Lions, Vikings head coach Mike Zimmer maintained that there would still be shared responsibilities between the two backs. But a total of 30 carries and eight receptions for McKinnon to eight and two (respectively) for Asiata in those games appears to belie something different.

In addition to his higher number of opportunities, McKinnon's 103-yard rushing performance came against the Bills' top-ranked rushing defense that had allowed an average of just 67.5 yards per game. Prior to the contest, Zimmer had asked his running backs to get three yards per carry after contact, which was higher than Chris Ivory's league-leading 2.68 yards after contact. Yet, McKinnon accomplished what he was asked, netting 57 yards after contact on 19 carries, for a perfect 3.0 average.

"I asked the backs to get three yards after contact," Zimmer told the Star Tribune following the game. "I thought we did a lot of good things there."

While Zimmer continues to downplay the importance of who is starting, it is hard to ignore the obvious. One of the two backs, McKinnon, has been given increased responsibility and he continues to improve his performance as more is given to him.

Looking back at McKinnon's season, it can be argued that things were heading in this direction all along. Taken in the third round of the draft to replace the departing Gerhart, McKinnon's arrival originally didn't move the meter much. A former running back, quarterback and cornerback in college, McKinnon would learn the NFL game and running back position behind Peterson and then take over for him when the Vikings decided to get out from under the aging Peterson's big contract.

But Peterson's off-the-field troubles quickly accelerated McKinnon's NFL tutorial. He had shown some flashes of talent in the preseason (both in rushing and receiving), and got just one carry in the first game, but since Peterson's absence following that game, McKinnon has gradually become a bigger part of the offense.

McKinnon backed up Asiata for four games and appeared to be learning as he went along, with only marginal opportunities and performances. But against the Atlanta Falcons, McKinnon shared equal time with Asiata, contributing to the offense's best game of the season. McKinnon rushed the ball 18 times (to Asiata's 20) and, thanks to a 55-yard romp, he led the team with 135 yards on the ground.

"He obviously flashed from the beginning and has done a good job making big plays," offensive coordinator Norv Turner said of McKinnon to the Star Tribune. "He's learning how to play in this league and he's become more consistent. He's finding the correct lanes; he's understanding defenses better."

He got his first start against Detroit (in which he had 82 all-purpose yards) and followed it up with a decent performance against Buffalo. He has not shown any need to look back.

"He improved a lot in protection from the first game he started to the second and that's a big part of playing running back in this league and our system certainly," Turner said. "He's making the normal progress that you'd like to see a rookie running back make."

Although relatively new to being a fulltime running back, McKinnon appears to have the tools for the job. At 5-9, 209 pounds, he isn't overly big, but he's compact and strong enough to fight through the line and break tackles in the open field. Once he gets into the open field, his speed (a 4.41 time in the 40 at the rookie combine) comes into play. While he has yet to display his wide-open sprinting ability (which we have seen from Peterson many times over the years), it may be only a matter of time. McKinnon's bursts of speed once he finds a small window are fun to watch.

McKinnon has been used a number of different ways in the Vikings backfield-- power runs, shotgun read options and pitch plays around end. Meanwhile, Asiata has been given the short yardage and goal-line responsibilities. Although McKinnon still needs work in pass protection, perhaps (despite the head coach's protests) designated roles are becoming defined.

"Jerick played well last week and that really has no bearing on what Matt has done. I still like Matt a lot," Zimmer said when asked about his stated intention to get both players carries. "I probably shouldn't pigeonhole myself by saying this number of reps or carries or something like that.

"Jerick has played well. I thought he did better in pass protection last week, I thought he ran the ball physically last week and he has a chance to make explosive plays and that has nothing to do with Matt. I still think Matt is a very, very good back. I think when you talk about change-of-pace sometimes a change-of-pace is different than what you think about. I still think that [Matt] gives us a lot of things."

One attribute that McKinnon exhibits is his patience and an ability to set up his blockers. He has shown that from the start, even before he got to the pros.

"What I found most encouraging is that [McKinnon] ran with his eyes -- he could set up blockers and make defenders miss creases when asked to do so," Matt Waldman of The Rookie Scouting Portfolio said in his pre-draft analysis of McKinnon.

Where Peterson demonstrated a lack of patience early in his career (and used to just bowl over oncoming tacklers when they got in his way), McKinnon will scan and set up the blocks and then burst into the opening, perhaps a result of once being a quarterback and needing to survey an opposing defense.

Now, certainly two starts is a small sample size on McKinnon, and it might be early to name him the Vikings running back of the future with so much uncertainty still surrounding Peterson. But McKinnon's two starts came against two of the best front sevens in the league, and he didn't wilt in either occasion. It's a small sample size, but definitely a good one.

The fact of the matter is that while Peterson continues to work through the slow

and grinding legal system to determine his future, McKinnon has the opportunity to grind out his present and possibly his future on the gridiron.

You can almost see the clouds beginning to part on the horizon.

Head over to VikingsJournal.com where you can read Bo Mitchell's fearless fantasy football predictions for week 8 and then join in the conversation on the Vikings Journal forums, where everything Purple is dissected and discussed.

Joe Oberle is a senior writer at VikingsJournal.com, covers the NFL for The Sports Post and is managing editor of Minnesota Golfer magazine. He is an author and longtime Minnesota-based writer.