The Vikings open their season looking to build on a 10-6 record and a playoff appearance in 2012. A difficult schedule awaits, starting Sunday in Detroit, the first of back-to-back NFC North road games to start the season. The Vikings swept the Lions last season. Here are three things you should know to prepare for the 2013 opener:

1. Vikings look to exploit Detroit's new-look offensive line.

The Lions revamped their offensive line and enter the season with three new starters — left tackle Riley Reiff, right tackle Jason Fox and rookie right guard Larry Warford. This should be an advantage for the Vikings, who tied for fifth in the NFL in sacks last season with 44.

The spotlight will shine brightest on Reiff, the successor to Jeff Backus, who retired after the 2012 season. Backus played 191 career games and set a franchise record with 187 consecutive starts in his 12-year career.

Reiff's first assignment comes against Jared Allen, who has collected 13.5 sacks, 7.5 tackles for loss and four forced fumbles in 11 career games against the Lions.

"Whoever is blocking him is going to really go to battle every single play and [can't afford] one play where you're not at your best because Jared can make you pay," Lions coach Jim Schwartz said. "A lot of forced fumbles, tipped balls, sacks, that's what he's known for. Those are the game-changing plays that he makes for Minnesota's defense."

2. Bush gives Vikings defense another cause for concern.

The Lions ranked last in the NFL in runs of 20 or more yards last season, according to Schwartz. The team believes it will improve in that area with the offseason acquisition of Reggie Bush.

Bush hurt the Vikings as a punt returner as a member of the New Orleans Saints, but he also proved to be an effective runner for Miami the past two seasons and he's always dangerous as a receiver.

The Lions hope Bush adds a new dimension to their offense, especially when opponents design their schemes to prevent deep passes to Calvin Johnson. The Vikings linebackers must be cognizant of Bush's ability to create big plays on short passes because he's so elusive in space.

"He has the potential of taking it to the house," Schwartz said. "He can take a short pass, a screen pass and he can make it into a big gain. He's an outlet for the quarterback. A guy like that is a tough matchup and sometimes you can check the ball down to him and still have a chance to make a first down from a third down and long."

3. First test for Josh Robinson as Winfield's replacement.

Schwartz made a revealing comment when discussing the Vikings' returning personnel.

"It's going to be interesting not seeing Antoine Winfield out there," he said.

Yes, Winfield is gone and reportedly had decided to retire. It's probably safe to assume the Lions will target his replacement, Josh Robinson, early to see how he responds in Winfield's old slot/nickel role.

Robinson had some rough moments in the preseason as he learns and adjusts to that slot role — a position he's never played. The website ProFootballFocus ranked Robinson last (113th overall) in its evaluation of NFL cornerbacks strictly in terms of coverage last season.

Robinson is listed as the starter at left cornerback, but he moves inside in nickel situations, with rookie Xavier Rhodes taking over outside.