EDEN PRAIRIE, Minn. —  Minnesota Vikings quarterbacks Tarvaris Jackson and Gus Frerotte will sit out the preseason finale at Dallas on Thursday night.

That opens the door for coaches to settle on a third quarterback _ either veteran Brooks Bollinger or rookie John David Booty.

Coach Brad Childress says he still has not decided who will start against the Cowboys. Each player will get a half with a chance to seal a spot on the roster behind Jackson and Frerotte.

Jackson has not played since injuring his knee against Baltimore two weeks ago. But he says he will be ready to start the regular-season opener against Green Bay on Sept. 8.

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