The Vikings typically hold a news conference with their starting quarterback on Wednesdays during the season. Mike Zimmer should send both Shaun Hill and Sam Bradford to the podium this week because it's unclear which guy will get the nod.

The Vikings might not even know yet. Teddy Bridgewater's devastating knee injury has forced them to operate on the fly.

Could Bradford be ready to play Sunday at Tennessee?

"Possible," Zimmer said.

How will you divide up first-team reps in practice?

"We're dividing them," Zimmer said.

This is not necessarily a case of Zimmer subterfuge. Sure, he'd love to keep the Titans guessing by not naming his starting quarterback until Sunday. He has nothing to gain by tipping his hand.

But that's assuming Zimmer already knows his plan, which he might not, because the team won't know whether Bradford feels comfortable enough with the offense until later this week.

The fact that Zimmer didn't name Hill outright as his starter for the opener suggests the Vikings at least are willing to consider Bradford despite his limited knowledge of the playbook. The team's tentative plan after trading for Bradford was to start Hill on Sunday.

The final answer shouldn't be a tough call by Friday. If Bradford gains enough grasp of Norv Turner's system by then and doesn't feel overwhelmed and isn't putting the offense at risk, give him the ball and let him go.

If Bradford remains uncertain about protections, verbiage or basic concepts, Hill should be the guy until Bradford catches up to speed. If there's any doubt, wait a week.

Bradford is like a college student cramming for a final exam after missing class all semester. He's racing against the clock.

"I've had to learn new offenses in the past," he said. "I don't know if I've had to learn one this fast or in this much of a hurry."

This should only be a one-week discussion. It's hard to envision Bradford not starting the home opener against the Green Bay Packers in Week 2.

He can't possibly learn the full playbook in five days. That's something that happens over the course of weeks, not days or hours.

Turner's staff likely is giving Bradford a condensed menu of plays in the short term and gradually will add to it as he gains more familiarity.

One thing working in Bradford's favor is that he's not walking into a wasteland. He's surrounded by Adrian Peterson and a top-five defense. That's a comfy security blanket for a guy whose head probably is spinning. The Vikings don't need him to save the day, just be a game manager for now.

Don't expect a repeat of Josh Freeman slinging 53 passes after only four practices with the first-team offense. The Vikings won't embarrass themselves again with another fiasco like that.

"We're probably not going to have to go out there and throw it 60 times a game and put up a lot of points," Bradford said. "But you've still got to come in, you've still got to put in the time and learn the new offense."

Even future Hall of Famer Brett Favre eased into things when he joined the Vikings in 2009. In his debut, Favre completed only 14 of 21 passes for 110 yards and one touchdown. He attempted 27 passes in the second game, accounting for 155 yards and two touchdowns. The script flipped in Week 3, of course.

Nobody is suggesting that Bradford can come close to replicating Favre's MVP-caliber season, but it's understandable if the formula initially relies heavily on Peterson's running and stout defense while Bradford gets comfortable with his new home.

General Manager Rick Spielman didn't commit two draft picks, including a first-rounder, to acquire Bradford with the idea that his ascension to starter will be a slow process. Everyone at Winter Park wants to expedite the inevitable.

There's a difference between being foolish and showing urgency. The Vikings can win Sunday with Hill at quarterback. But he's eventually going to return to his backup role behind Bradford.

It serves no purpose to make that determination for the opener until they evaluate Bradford's comprehension of the offense after a weeklong cram session.

Chip Scoggins • chip.scoggins@startribune.com