Now that Backus is retired, the job belongs to Reiff and the first challenge this season will be a formidable one.
Reiff and the Lions host the Minnesota Vikings this weekend, which means a visit from pass rushing star Jared Allen. Reiff, a first-round draft pick in 2012, will have an early chance to show he's ready for a bigger role as part of a new-look offensive line in Detroit.
"I'm just improving every week," Reiff said. "Jared's a great player. He's respected around the league. I'm just going to go out there and play."
The Lions lost Backus and free-agent tackle Gosder Cherilus in the offseason, so there will be some new faces in important spots up front. Reiff, whom the Lions drafted out of Iowa last year, is stepping in at left tackle, while Jason Fox is listed atop the depth chart at the other tackle spot.
Led by quarterback Matthew Stafford and receiver Calvin Johnson, Detroit's offense has the potential to be dynamic — so it's important that the changes on the offensive line are as seamless as possible.
Holdovers Dominic Raiola and Rob Sims are back at center and one of the guard spots. Tackle Corey Hilliard and guards Dylan Gandy and Larry Warford are also in the mix. Warford was a third-round pick in this year's draft.
As for Allen, he's a 31-year-old veteran with 117 career sacks — and it will certainly be different this weekend going up against someone other than Backus.
"It makes you realize that you're getting up there in years when guys you've been playing against your whole career start retiring. I am just looking forward to the new challenge. The new young kid is coming in and getting after it," Allen said. "Young guys are trying to make a name in this league, too. How else do you make a name other than beating established players? I remember when I was young, I got to go up against Orlando Pace and I was licking my chops, I was excited."
Allen has 13½ sacks in 11 career games against the Lions, including a pair of three-sack games in 2011.
"You're playing the best. Jared's proven it year in and year out," Sims said. "There's nothing timid about Riley. There's no fear in Riley. He's got kind of like that monotone — just goes about his business. Kind of like how Jeff did."
Backus was a first-round pick in 2001 and played with the Lions his whole career, missing only one game. He started his first 186 games — plus one playoff game — before a hamstring injury forced him to miss last year's Thanksgiving matchup against the Houston Texans.
That was an early chance for Reiff to show what he could do on a big stage — and coach Jim Schwartz hopes that experience will prove valuable now that the young tackle is being asked to do more.
"This isn't Riley Reiff's first start in the NFL. He started against a very good Houston team with some very good outside pass rushers last year — stepped in and did a nice job on a very short week," Schwartz said. "That's a very important matchup in this game. Jared Allen's a guy that makes a bunch of sacks, turns the ball over a lot, can force you into holding penalties. Riley, or whoever's lined up against Jared Allen, is going to have to play their best."
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