Jeremiah Sirles should not be able to call this week of practices "business as usual."

But he can — and he is right — for an offensive line undergoing yet another rotation of their tackle carousel. The Vikings have started four different tackle combinations through nine games and, on Sunday against the Cardinals, they're expected to go back to lineup No. 3, which had T.J. Clemmings at left tackle and Sirles at right tackle, following left tackle Jake Long's torn Achilles' tendon last week.

"You never expect this to happen," Sirles said. "You never expect to lose essentially four starting tackles in a year, but it's the nature of the game."

Has it been four? They're only in Week 11, but it's easy to lose track of just how many tackle departures the Vikings have suffered between Matt Kalil, Andre Smith, Long, Mike Harris and the retirement of Phil Loadholt.

"It's been difficult," coach Mike Zimmer said. "You go back and look at, what is it — five, six tackles that we don't have that we started out with or something like that."

So they again likely will turn to the Clemmings-Sirles tackle duo, which started games against the Texans and Eagles, vs. a strong Cardinals pass rush featuring former Patriots star Chandler Jones, who has seven sacks from his outside linebacker spot this season, as well as linebacker Markus Golden and defensive tackle Calais Campbell. The trio combines for 16 of Arizona's 24 sacks on the year.

They're just another top-10 NFL pass rush the Vikings watched on film this week. They already have faced the Titans, Panthers, Eagles, Redskins, Bears and now Cardinals — six of the league's top nine sack-producing teams.

However, the latest tackle injury did prompt an unusual turn of events this week at Winter Park.

After the 26-20 loss in Washington, left guard Alex Boone immediately lobbied offensive line coach Tony Sparano to move him to left tackle. Six weeks ago, Boone said he "didn't want to think" about playing tackle because it'd "been so long." That was before two more tackles were placed on injured reserve.

Boone is expected to stay at guard but said his past experience at left tackle, where he started at Ohio State eight years ago, made him a logical consideration.

"I just feel it'd be an easier move for me than T.J.," Boone said.

"But at the end of the day, it's up to the coaches," Boone added. "They're going to put the best five out there, and I trust in them to do that. We'll see how that goes."

The Vikings' options are limited with a combined zero career snaps between two backup tackles in rookies Willie Beavers and newly signed Rashod Hill. Quarterback Sam Bradford expressed confidence in Clemmings and Sirles, saying "we feel confident in them because they've been out there." Their last start together, however, was nightmarish for Bradford — he took 19 hits, including six sacks, in the first loss in Philadelphia.

They still remain confident, perhaps exemplified best when Sirles laughed about Boone stumping for a move to tackle.

"Alex says a lot of things," Sirles said. "You just kind of let Alex talk, and let him deal with everything."

The Cardinals have their own protection issues, having allowed 27 sacks this season — more than the Vikings (24) and fourth most in the league. They'll trot out a young left tackle for his third career NFL start, John Wetzel, after losing starter Jared Veldheer (torn triceps) two weeks ago.

Arizona's offensive line issues still pale in comparison to the challenge facing the Vikings' remaining tackles, who are burdened with the critical task of keeping Bradford upright.

"I went through [the loss of multiple left tackles] one year in Pittsburgh," Cardinals coach Bruce Arians recalled. "You just keep scratching your head like, 'How can I help the guy?' You know, the more you try to help him, the less help he gets because defenses know how to stop that help.

"It's hard, especially at left tackle, to have a revolving door."