The Vikings began reporting to the first training camp Tuesday at the TCO Performance Center in Eagan. The first full-team practice is Saturday. Check here for new details on tickets, parking and times.

The Star Tribune is taking a look at each position group. Wednesday: Offensive linemen.

On the 90-man roster: 15 offensive linemen

Locks: LT Riley Reiff, LG Nick Easton, C Pat Elflein, RG Mike Remmers, RT Rashod Hill, RT Brian O'Neill

Good bets: G Tom Compton, G Danny Isidora

On the bubble: T Aviante Collins, G Colby Gossett, C Josh Andrews

Practice squad candidates: C Cornelius Edison, T Storm Norton, G Cedrick Lang and G Chris Gonzalez

Changes
(+) Drafted tackle Brian O'Neill in the second round (62nd overall) out of Pittsburgh. … Applied second-round tender to guard Nick Easton, paying him $2.9 million this season. … Signed guard Tom Compton to a one-year, $900,000 contract with $250,000 guaranteed.

(-) Center/guard Joe Berger retired. … Guard/tackle Jeremiah Sirles signed a one-year, $880,000 contract with the Panthers.

Situation
Tony Sparano's passing at age 56 casts a dark cloud on the start of this year's training camp. On the field, assistant O-line coach Andrew Janocko takes over as interim leader of a group with some question marks. Will Riley Rieff pick up his play to September/October levels again? Can Pat Elflein build on a promising rookie season despite offseason ankle surgery? How will Mike Remmers handle the apparent full-time move to guard? Can a slimmed-down Rashod Hill be the answer at right tackle? Elflein could either be limited or start camp on the Physically Unable to Perform list as he continues his rehab from offseason ankle surgery. The sooner he returns, the sooner the Vikings can see the expected Week 1 lineup for the first time in practice. Hill losing 12 pounds could go a long way toward keeping up in the zone-blocking system this season.

With stellar skill talent and an $84 million quarterback, the offensive line is the assumed weak link. They've got the opportunity to prove otherwise after a disappointing finish in last year's playoffs.

Top question
Can the Vikings offensive line take another step forward? There's plenty of room for improvement between Remmers and Hill settling into the right side of the line. They caught lightning in a bottle last season with Case Keenum fielding a top pressure rate, yet being one of the least-sacked quarterbacks during the regular season. The Vikings can't afford to bank on such evasiveness and/or luck from Kirk Cousins, who is mobile and durable, but does his best work when kept clean.

What you should know
Not since the 1994 Colts, which drafted Marshall Faulk, has an NFL offense bounced back from a dead-last rushing attack to rank top 10 the following season. That's what the 2017 Vikings did. Give the offensive line some credit for this next time you're debating them around the water cooler. The Vikings' 122.3 rushing yards per game ranked seventh, while 100 rushing first downs ranked 10th.

Notable number
Seven offensive linemen — The Vikings have had at least seven offensive linemen play 20 percent or more of the season — a minimum of 3.2 games — in three of the last four years. That's remarkably tough luck with injuries in one position group. You'll see some variation of this statistic repeated as reserves compete for roster spots this summer.

Top competition
Backup interior O-line — The pecking order is well established at tackle, especially with Hill taking nearly all the first-team reps at right tackle this spring. Should Remmers stick at right guard throughout the preseason, then Compton, Isidora and Andrews are among those vying for the remaining roster spots.