Christian Ponder's status for 2013 is the No. 1 question Minnesota must answer.
It hasn't been the type of season Minnesota envisioned for itself.
With the early part of the schedule featuring some of the Vikings' easier opponents, the Vikings were hoping to accumulate victories early to compensate for the losses that will surely come later.
But four weeks in the Vikings are 1-3 and their playoff aspirations are hanging on by a thread.
After a 34-27 win over the Pittsburgh Steelers in London, that thread got a bit thicker. It was a nice showing, but the questions remain.
There are plenty of potholes that need to be fixed for the 2013 journey to experience a smoother journey from here.
This slideshow assesses five of the bigger questions that will determine Minnesota's success moving forward.
After a sophomore season that ended with a Pro Bowl appearance, Kyle Rudolph's third year has been a disappointment.
After taking a massive leap in his second season (53 receptions, 493 receiving yards and nine touchdown receptions) that ended with a Pro Bowl MVP, expectations were increased greatly for the 2011 second round pick.
At 6'6" and 258 pounds, the size and athleticism is there for him to be one of the game's most dangerous threats in the red zone. Yet, he only has 12 receptions for 103 yards and a touchdown this season.
The problem with Rudolph is consistency. He can't seem to be a difference maker on a weekly basis.
Part of the problem there is the play at quarterback.
Receivers, across the board, cannot be successful if their quarterback can't get them the ball. But Rudolph isn't without fault either.
He can do a better job breaking away from his defender and making himself seen.
Just look at the win over Pittsburgh.
Minnesota's passing game was working well, by its standard, and Rudolph caught two passes for six yards on two targets.
Maybe if Cassel sticks as the starter and the passing game can do this more frequently, Rudolph's numbers will gradually improve as those two get comfortable.
Maybe they won't.
But Rudolph is better than this and it's painful to watch a talented player perform beneath his abilities.
Josh Robinson has struggled in 2013.
Maybe this is as good as it gets. Maybe this what the Vikings are.
The loss of Antoine Winfield was expected to hurt. But maybe not this badly.
Minnesota boasts the league's WORST pass defense (326 yards per game).
With injuries to cornerback Chris Cook and safety Jamarca Sanford, the unit was depleted against Pittsburgh. Pro Football Talk said Cook may or may not be back in time for the Week 6 battle with Carolina.
The Josh Robinson experiment as a starter isn't working. It's time to get rookie Xavier Rhodes in. Robinson has been targeted and torn apart by opposing quarterbacks, including against Pittsburgh when Antonio Brown drew a pass interference call that resulted in a 48-yard penalty.
He's struggling, and needs to be on the field less.
Outside of that, Minnesota needs Cook and Sanford to heal up and get back and hope the pass rush can disrupt the opposition's passing attack.
That will be key to lessening the aerial yardage allowed.
Phil Loadholt has been among the disappointments on the offensive line.
Many considered this unit to be one of the Vikings' greatest strengths entering 2013.
It allowed the 11th fewest sacks in 2012 (32; two per game) but allowed 10 in the first three games (3.33 per game).
The group rebounded against Pittsburgh, allowing just one sack and falling to 15th most allowed.
Part of the problem with the sacks had been Christian Ponder. His pocket presence isn't what it should be and he often holds the ball too long. But in the three games with him under center there were plenty of sacks that were on the offensive line.
Matt Cassel got the ball out quicker on a more consistent basis in Week 4 and should he retain the job in Week 6 that will help limit the sacks.
On the ground game, the holes that were there in 2012 haven't frequently been there in 2013. That has limited the effectiveness of Adrian Peterson, who also broke out in Week 4 for 140 yards on 23 carries (6.1 yards per carry) with two touchdowns.
Prior to Week 4 Peterson hadn't gotten over 100 yards rushing.
As was the case for many areas, Week 4 was a better week for the offensive line.
With all five starters back from a unit that was considered one of the best in 2012, there's reason to believe things will get better.
And given the complexion of the Vikings, it has to should Minnesota want to return to the postseason.
Jerome Felton may very well be the cog that drives Minnesota's ground game.
Strapped with a three-game suspension to open 2013, Jerome Felton could only sit and watch as Adrian Peterson failed to rush for more than 100 yards in the season's first three contests.
In Week 4, it was his time to shine and he helped Peterson eclipse that 100-yard plateau to the tune of 140 yards on 23 carries with two touchdowns.
Was Felton the difference in the ground game's struggles?
Prior to Felton, Peterson had never eclipsed 1,800 yards. One season together and he falls 9 yards shy of setting the single-season rushing record.
One game in to their reunion, the answer seems to be a simple yes.
But it's just one game.
And with aforementioned troubles scattered across the offensive line, Minnesota has its work cut out for itself to improve the 21st-rated running game (104.8 yards per game).
The battle is on between Christian Ponder (left) and Matt Cassel to be Minnesota's quarterback.
The answer to this question seems simple to the outside world.
After the nine-year vet completed 16 of 25 passes for 248 yards with two touchdowns and no interceptions, fans are ready for the Cassel era to take shape in 2013.
He led the team to its first victory of the season and ignited what was a lifeless aerial attack.
In the eyes of most, he should start.
“He’s more vocal,’’ Adrian Peterson said to the Star Tribune of Cassel. “He was out there saying his two cents worth in the huddle and you see guys buying into it, and keeping the huddle together and that’s all you can ask for … He did a good job.’’
That sounds like another endorsement.
But the problem for Minnesota is that it has so much invested in Ponder. He was its first-round pick in 2011 and the franchise put its future in his hands.
Is it ready to concede that Ponder was a failure? Or will Ponder's rib injury magically persist throughout the season and enable the Vikings to save face?
If Minnesota is looking for the best shot to win in Week 6, Cassel will start. If it's still looking to develop Ponder for the future, then the former Florida State Seminole will start.
Barring the rib injury sticking, we'll get a better idea of the direction of this franchise when the Week 6 starter is announced.