Four down, four to go.

The Vikings signed half of their eight-man 2018 draft class Thursday, a day before rookies, undrafted signings and tryout players take the field for rookie minicamp.

Kicker Daniel Carlson, guard Colby Gossett, defensive end Ade Aruna and linebacker Devante Downs inked their boilerplate four-year deals. All rookie contracts featured slotted salaries based on draft position, according to the NFL's collective bargaining agreement.

The Vikings' top four picks — cornerback Mike Hughes, tackle Brian O'Neill, defensive tackle Jayln Holmes and tight end Tyler Conklin — are left to sign. Most are still expected to participate Friday at the start of a three-day minicamp. In lieu of a signed contract rookies typically sign a participation agreement, which is basically an injury waiver.

Carlson, a fifth-round pick taken 157th overall, signed a four-year deal worth about $2.7 million, based on last year's contract at the same draft spot. Gossett (213th overall), Aruna (218th) and Downs (225th) have deals worth about $2.5 million with guarantees around $100,000 each.

Downs, the former Cal linebacker, is the only Vikings rookie not expected to participate during on-field drills this weekend. Downs is coming off a significant knee injury that ended his college career midway through last season.

"I was having a pretty good year," Downs said, "I was two-time player of the week in my conference and it just happened at a bad time. But like I said, everything happens for a reason."