When Vikings coaches examined the game film from Saturday’s 20-7 exhibition win at Seattle, they watched a team that is carving an identity in several areas while trying to mask deficiencies in others.

The starters were on display for most of the first half, offering a glimpse into where this team is headed offensively and which young playmakers can make a difference on the 53-man roster.

“We seemed to be composed and really seemed to have a handle on what we wanted to get accomplished,” coach Leslie Frazier said.

Here is a positional breakdown of the Vikings’ starters (and a few notable others, for better or worse) as they prepare for Dallas on Saturday at the Metrodome.

QUARTERBACKS: B

Donovan McNabb‘s only miscue was failing to punctuate an impressive drive with a touchdown. After driving 81 yards downfield and spreading the ball to five different receivers, McNabb attempted a batted-down screen pass and overthrew tight end Kyle Rudolph at midfield. McNabb (6 of 8, 81 yards) didn’t take any chances and kept his passes in the short to intermediate range, likely as a result of an offensive line in transition. This is the McNabb the Vikings will take every week – composed, avoiding turnovers.

OFFENSIVE LINE: B-MINUS

When left tackle Charlie Johnson allowed defensive end Raheem Brock to go untouched for a sack early in the first quarter, it appeared to be a long night for the offensive line. But the group rebounded on the second series and provided just enough push up the middle for Adrian Peterson (six rushes, 16 yards) and Toby Gerhart (6-21). Rushing plays to the outside didn’t seem to work, and it’s obvious the Vikings are favoring quick passes because the line can’t maintain a clean pocket for long periods. But given the personnel, this group had positive moments.

RUNNING BACK: B

Peterson held on to two screen passes, which is more than he can say about his recent practices. Certainly this is not a position of concern, and Peterson looked fresh on his six carries and two catches for 11 yards. The low yardage total was affected by two left sweep plays with nowhere to go.

Once again, Lorenzo Booker (seven rushes, 37 yards) was loose with the ball, getting stripped in the open field. He’s lucky the ball bounced out of bounds. He’s great in space, but he’s got to secure the ball.

FULLBACK: C-MINUS

Ryan D’Imperio didn’t do much to claim a position that tight ends Jim Kleinsasser and Jeff Dugan can play in a hybrid role. Missed two lead-block assignments that resulted in loss of yardage. Caught one pass for nine yards.

WIDE RECEIVER: B

Save for Michael Jenkins‘ 21-yard sideline catch, the starters didn’t see much action here. Bernard Berrian wasn’t even targeted. But the team’s most intriguing position battle is taking place at backup receiver, where eight fringe players are fighting for two spots. Devin Aromashodu and Juaquin Iglesias, each with two catches for 30 yards, helped their cause by showing good footwork and athleticism. Where was Jaymar Johnson (one target deep, no catches) after such a great training camp?

TIGHT END: B-PLUS

Though he’s not the most refined blocker, Rudolph showed his passing-game capabilities by hauling in a 17-yard McNabb pass that was low and behind him. Kleinsasser (one catch, 23 yards) did his part as a reliable lead blocker.

DEFENSIVE LINE: B-PLUS

Ends Jared Allen and Brian Robison each penetrated the backfield but couldn’t finish. Standouts came from the second-team unit. There’s real depth here. Tackle Letroy Guion, tackle Christian Ballard and end Everson Griffen were disruptive against the Seahawks’ first-stringers.

LINEBACKERS: B-PLUS

E.J. Henderson blasted through the middle to stuff a run for a loss of two, and Chad Greenway recorded one open-field tackle in limited action. The weak side is still Erin Henderson‘s spot to lose, and despite obvious athleticism, the Vikings will try to keep him motivated and disciplined. Jasper Brinkley got weak-side reps on the second series, which could be a motivational ploy for Henderson, who finished with five tackles and a vicious blindside hit. Brinkley got exposed in the passing game by Seahawks quarterback Charlie Whitehurst.

SECONDARY: C

This group would have graded higher if not for some confusing second-half play, particularly at safety. No defense should allow Whitehurst to complete 11 of his first 12 passes, including one for a touchdown. He kept throwing slants, and the Vikings never adjusted.

Cornerbacks Cedric Griffin, Antoine Winfield, Chris Cook and Marcus Sherels forced quarterback Tarvaris Jackson to dump the ball off and eliminated the deep ball. Cook improved his play after a rocky start, running step for step with Sidney Rice on a go route. And Sherels is really fast, as evidenced by his 64-yard interception touchdown.

What’s going on at safety? Husain Abdullah is the only player taking command of a starting spot. Tyrell Johnson and Jamarca Sanford failed to make standout plays, and though rookie Mistral Raymond has potential, he’s still raw.

SPECIAL TEAMS: A

The Vikings’ kickoff and punt return coverage has been impressive, keeping opponents inside of the 28-yard line on six preseason kickoffs. On nine Chris Kluwe punts, opponents are averaging less than two yards per return.

Follow Jeremy Fowler at twitter.com/vikingsnow.