Kirk Cousins not only question facing Vikings going into camp

The Minnesota Vikings open training camp July 28 at TCO Performance Center in Eagan, Minnesota. Here's a closer look at what to expect.

Top storyline: By the time training camp rolls around, Kirk Cousins will have had about 3½ months to learn the Vikings' playbook. His summer plans included going over the concepts he didn't grasp during the initial install and discussing how he wants certain plays designed with his coaches. Cousins' feel for the offense and how the quarterback executes the scheme is not only the storyline of training camp but of the entire 2018 season. However, not everything rests on the shoulders of the Vikings' $84 million investment. Minnesota still has several unanswered questions with its offensive line, which lost its leader after the death of veteran coach Tony Sparano at age 56 on Sunday. Training camp will serve as a time for continued experiment among its starting five until the Vikings find which combination works best. Pat Elflein is on schedule to return for camp, meaning Nick Easton will move back to left guard. It's the right side of the line that remains up in the air between where Mike Remmers will play and who will fill the remaining spot. In each of the past two seasons, issues on the O-line caused mostly by injuries led the Vikings to slip down the stretch. In hopes of avoiding a repeat of that this season, it will be crucial for Minnesota to find the right combination to protect Cousins.

QB depth chart: The Vikings know the importance of having a capable backup quarterback after former second-stringer Case Keenum helped lead them to last season's NFC Championship Game. Trevor Siemian brings invaluable experience as a starter and impressed coaches with his accuracy and ability to operate the huddle more quickly as the spring wore on. Minnesota hopes it never encounters a situation where Cousins isn't able to play, but having Siemian in the wings is a solid insurance policy. Behind Siemian is second-year pro Kyle Sloter, who continues to be held in high regard by the franchise despite no regular-season reps. The Vikings' fourth QB in training camp is Peter Pujals, an undrafted free agent from Holy Cross who signed with Minnesota in May.

Bubble watch: A handful of veterans might be on the verge of being released when the Vikings finalize their 53-man roster. Brian Robison took a $2 million pay cut to return to Minnesota for his 12th season. What role he fills in the defensive-line rotation and whether younger players like Stephen Weatherly and Tashawn Bower make a push for his position will be determined in camp. First-round cornerback Mike Hughes will compete for a job returning punts and kickoffs with longtime special-teams vet Marcus Sherels. Kai Forbath enters training camp in competition with fifth-round pick Daniel Carlson. Undrafted free-agent cornerback Holton Hill received praise from coach Mike Zimmer and general manager Rick Spielman during the spring and could earn a roster spot.

This rookie could start: Minnesota might not be in any rush to pitch a competition at nickel corner between Hughes and Mackensie Alexander, but the first-round pick should see time in the return game early on. Aside from Hughes, kicker Carlson probably has the best shot of any rookie to win a starting job.

Changes on defense: After Hughes was drafted in April, Zimmer hinted at wanting to experiment with four-cornerback looks when the Vikings are in various nickel packages given the flexibility and depth they have at the position. Terence Newman could certainly be a part of those substitution packages as a corner, but the veteran might be better suited as a rotational defensive back, particularly after getting ample reps at safety this offseason. Pro Bowl linebacker Anthony Barr might also see his role transition after working more on the outside this spring. Barr used to rush the passer often in college (23.5 sacks in 2012-13 at UCLA) but has spent his four NFL seasons primarily dropping back into coverage. One of the Vikings' missions this offseason was to shore up their defensive-line rotation. Barr might soon become part of that if his reps in the spring are any indication of future usage.

Competition in the receiving corps: The No. 3 receiver position is one of the more intriguing battles in training camp. At the end of the spring, Laquon Treadwell had emerged as the leading candidate for the job, but he'll have to ward off the likes of Stacy Coley, Kendall Wright and Brandon Zylstra over the next month. Minnesota kept six receivers on the 53-man roster last season and has a deep crop of players to sort through behind Adam Thielen and Stefon Diggs.

Contract watch: The Vikings have a handful of contract situations to work through in the near future. Last year Minnesota awarded extensions to Xavier Rhodes, Everson Griffen and Linval Joseph before heading down to Mankato or at the beginning of training camp. Danielle Hunter signed a five-year extension at the end of June, leaving Diggs and Barr on the verge of playing into a contract year unless the players and their representation are able to work out an extension with the front office before the season.