The Vikings’ 12 draft picks, along with their 10 undrafted free agents, will officially begin their NFL careers on Friday, when they report to the team’s facility in Eagan for the start of the Vikings’ annual rookie minicamp.

The team ordinarily likes to make quick work of signing its draft class, often striving to get all of its picks under contract before starting rookie workouts on Friday. This year, however, that process could take a little longer for at least some of the Vikings’ rookies.

Minnesota currently has $1.682 million in salary cap space, according to NFLPA data, and would need about $2.78 million, in total, to sign its draft class. That means the Vikings need to clear about $1.1 million in space before they can get their entire draft class signed (though in reality, the Vikings will likely need more than that for a couple reasons we’ll get into later).

First, a brief note about how all this works: Because of the NFL’s top-51, a team’s offseason salary cap consists of the base salaries for the players with the 51 highest cap figures on the roster, plus bonuses and likely-to-be-earned incentives for all other players on the roster. In other words, when the Vikings sign a draft pick, they’ll only count that player’s base salary against the cap if his overall cap number is one of the 51 highest on their roster. All other draft picks — as well as undrafted free agents — will only have their signing bonuses counting against the offseason cap.

By my calculations this morning, only four Vikings draft picks — first-rounder Garrett Bradbury, second-rounder Irv Smith Jr., third-rounder Alexander Mattison and fourth-rounder Dru Samia — have cap hits large enough to land them in the Vikings’ top-51 contracts. Those four players should bump linebacker Devante Downs, cornerback Holton Hill and running backs Mike Boone and Roc Thomas out of the Vikings’ top 51. Defensive lineman Ifeadi Odenigbo, who signed a new two-year contract with a $125,000 signing bonus in January, currently has the Vikings’ 51st contract, with a cap hit of $632,500. Because all of the Vikings’ other draft picks have cap hits below that amount, only their signing bonuses count against the cap in the offseason. The signing bonuses, plus the changes to the Vikings’ top 51 base salaries, are worth a total of about $2.78 million. The Vikings could start signing their later draft picks immediately, of course, but at a bare minimum, they’ll have to make a move before they sign Bradbury, who’d add $1.772 million to their cap once he displaces a player from the top 51.

Now for that piece of the puzzle we said we’d revisit later: The NFL’s cap rules change at the start of the regular season, when rosters are reduced from 90 to 53 players. At that point, the top-51 rule goes away and teams must count every salary — from players on the active roster to those on practice squads, injured reserve or the physically-unable-to-perform list — against the cap. That means teams typically need several million more in cap space by the start of the regular season, especially if they have a high-priced player that lands on injured reserve or release a player with dead money charges. And as the Vikings certainly know from last year, it’s important to have extra cap space to address in-season needs that might arise — like, for example, a new kicker in Week 3 after a rookie misses three field goals against the division rival.

So it’s reasonable to assume the Vikings will be looking to clear around $3-5 million in cap space, through various means, between now and the start of the regular season. Speculation this week has centered on tight end Kyle Rudolph, with several reports over the weekend that the Vikings had received trade inquiries about the 29-year-old (as well as cornerbacks Xavier Rhodes and Trae Waynes). Rudolph told the Star Tribune on Friday night it was “awesome” the team had drafted Smith, and the Vikings have said both players can have a role in their 2019 offense, due to the differences in their games.

The Vikings figure to have quarterback Kirk Cousins under center more often in their revamped offense, and Smith lined up as a fullback at times in college, so it’s conceivable the Vikings could spend enough time in two-tight end sets, with Rudolph on the line of scrimmage and Smith either in the backfield or in the slot, to make it worth their while to keep both players.

There’s a price for everything, though, and as Andrew Krammer and I talked about on the latest Access Vikings podcast, the question could be what price the Vikings put on Rudolph if his role changes in 2019. He’s scheduled to count for $7.625 million against the cap, and told the Star Tribune last month he’d listen to the idea of reworking his deal, especially if it provided guaranteed money in exchange for a reduction in his salary. If the Vikings do approach him about a restructure, Rudolph would have to weigh the chance to prolong his career with the team that drafted him — and in a city where he’s had an immeasurable impact through his community work — against the possibility of going to a team like the Patriots, who didn’t draft a replacement for the retired Rob Gronkowski.

“This is part of the NFL, younger guys coming in,” Rudolph said on Friday night. “But I truly believe my best football is still ahead of me. Whether it’s here or not, that’s not my decision. But I do know the football I have left in me, and that’s all I can control.”

A move affecting Rudolph’s status might be among the more obvious possibilities for the Vikings, but it’s certainly not the only one. In any case, the team has some financial rearranging to do to sign its draft class, as General Manager Rick Spielman alluded to last week.

“Once [vice president of football operations] Rob [Brzezinski] gets out of cap jail he’ll come out and figure it out,” Spielman deadpanned. “We have a plan. Like I said, we’ve planned this process all the way out. This is not something that we’re just shooting at the hip. There’s a method and there’s a plan in place from a budgetary standpoint from what we need to do and how we need to get there.”