MINNEAPOLIS (AP) Yes, Brock Osweiler has a contract befitting a franchise player, but he joined the Houston Texans this year with only seven career starts.
Sam Bradford was once the first overall pick in the draft, but if the Minnesota Vikings finish with a winning record this season this will be the first time he's experienced that in his professional career.
Quality quarterback performance has never been more important in the present-day NFL, but what has also become clear is that success is possible without one of the league's established elite taking the snaps.
Dominant defense, with reigning Super Bowl champion Denver as the prime exhibit, is a must have.
That's primarily why the Texans (3-1) and Vikings (4-0) are winning, and they're not alone.
Philadelphia (rookie Carson Wentz), New England (suspended Tom Brady), Denver (first-time starter Trevor Siemian), St. Louis (career fill-in Case Keenum) and Dallas (rookie Dak Prescott) also have aided less-than-ideal blueprints at quarterback this season with defenses that rank in the top 10 in points allowed.
''When you look at the Vikings defense, you're looking at a terrific defense,'' Osweiler said. ''We know the challenge we have going on the road.''
The Vikings will face one on Sunday as well. Even without superstar defensive end J.J. Watt, the Texans have been difficult to move the ball against.
''They're very sound. Very rarely does it look like guys are out of place,'' Bradford said. ''They're just playing really good football on that side right now.''
Here are some key angles to follow for the game:
THE BLAIR WALSH PROJECT: Vikings kicker Blair Walsh ranks 28th in the NFL with a 72.7 percent field goal rate that wouldn't be as concerning if he hadn't had some struggles the past few years and the infamous miss of a 27-yard try at the end of the one-point loss to the Seattle Seahawks in the playoffs last season. Coach Mike Zimmer ominously replied ''not yet'' when asked this week whether the team would bring in any free agents to compete for the job.
In addition to three failed field goals, Walsh has missed two extra points.
''That may cost us someday,'' special teams coordinator Mike Priefer said. ''So we're hoping to rectify that situation and help him go out and make all his kicks.''
BROWN'S BACK: The Texans should get a boost by the expected return of veteran left tackle Duane Brown. He missed the first four games this season while recovering from January surgery to repair a torn quadriceps muscle. There's nobody more eager to have Brown back than Osweiler, who will work with Brown in a game for the first time on Sunday.
''I don't really foresee any challenges between Duane and myself,'' Osweiler said. ''Just all smiles there. Any time you get a player back like Duane, at quarterback there's nothing you can do but smile with that one.''
CLOWNEY'S PROGRESS: Defensive end Jadeveon Clowney is finally healthy and contributing for the Texans after failing to make an impact over his first two injury-filled seasons in the league. The first overall pick in the 2014 draft will start his fifth straight game on Sunday, which will be the first time in any of his NFL seasons that he's played that many in a row. Clowney's emergence has been well-timed with the loss of Watt, who had season-ending back surgery last week. Clowney had a sack and two hits on Tennessee quarterback Marcus Mariota in the previous game, and he has five sacks in his past eight regular-season games.
VIKINGS VULNERABILITY: Clowney has played both end spots in Houston's 3-4 scheme since Watt has been out, so both Vikings tackles will need to be prepared to block the 6-foot-5, 270-pound product of South Carolina. T.J. Clemmings has taken over on Bradford's blind side on the left, with Matt Kalil likely out for the season following hip surgery. On the right side, Andre Smith left the previous game with an injury to his right arm. Jeremiah Sirles stepped in and will play again if Smith doesn't.
Minnesota's offensive line has had its trouble, with only center Joe Berger the only starter in the same place as last season and the running game lagging at the bottom of the league with only 64.3 yards per game, but Bradford's quick release has helped with the pass protection. He wasn't sacked in the previous game.
RARE VISIT: The Vikings have won all three matchups with the Texans, who entered the NFL in 2002 and have made only one prior regular-season visit to Minnesota. The Vikings beat Houston 28-21 at the Metrodome in 2008, behind three touchdown passes by Gus Frerotte and an end zone interception of Texans quarterback Sage Rosenfels.
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