Posted by ESPN.com's Kevin Seifert
MINNEAPOLIS -- About 40 minutes before kickoff Saturday night, Minnesota Vikings coach Brad Childress looked in the eyes of quarterback Tarvaris Jackson. Childress asked Jackson if he thought he could play against the Pittsburgh Steelers.
Jackson, a week removed from spraining his right knee, responded honestly: He wasn't up to it.
"It wasn't hard at all [to admit it]," Jackson said. "I wasn't ready to play. Under these circumstances, I wasn't ready to play."
Jackson watched as Gus Frerotte and rookie John David Booty handled the quarterback duties in a 12-10 loss to the Steelers. Jackson said he does not know if he will play in Thursday's preseason finale at Dallas, but Jackson seemed certain he will be ready for the Vikings' Sept. 8 season opener at Green Bay.
"No doubt at all," Jackson said.
At the very least, Jackson will start the game with a much lighter tuneup that originally intended; he has played only two quarters and accounted for 22 percent of the Vikings' preseason passes (22 of 100) this summer.
Jackson knows how important preseason repetitions are for a developing quarterback. Saturday night, however, he didn't seem to think he had much of a choice.
"I would love to have played today and possibly Thursday," he said. "But it didn't work out like that."
The knee injury is Jackson's fifth significant ailment since he was drafted in 2006; it occurred at the end of a run Aug. 14 at Baltimore. Instead of sliding, Jackson put his shoulder down to gain an extra two yards, contributing to the injury.
Speaking for the first time since that night, Jackson said he doesn't plan to start sliding to protect his health.
"Naw," he said. "Still not sliding."
It wasn't clear if Jackson was serious or joking. And as it turned out, ambiguity was a perfect metaphor for his uncertain status.