Minnesota Vikings quarterback Brett Favre warms up for a NFL preseason football game against the Kansas City Chiefs, Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Andy King)

Minnesota Vikings quarterback Brett Favre looks over a play chart with Vikings offensive coordinator Darrell Bevell, right, and quarterback Sage Rosenfels, left, who did not suit-up for the game, after the Vikings first offensive series during the first quarter of a NFL preseason football game against the Kansas City Chiefs on Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Tom Olmscheid)

Minnesota Vikings quarterback Brett Favre, left, hands off to Vikings running back Adrian Peterson during the first quarter of a NFL preseason football game against the Kansas City Chiefs, Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Andy King)

Minnesota Vikings quarterback Brett Favre (4) is hit as he throws by Kansas City Chiefs' Corie Mays in the first quarter of their NFL preseason football game, Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Andy King)

Minnesota Vikings' quarterback Brett Favre (4) looks to pass against the Kansas City Chiefs during the first half of a NFL preseason football game, Friday, Aug. 21, 2009 in Minneapolis. (AP Photo/Paul Battaglia)

Minnesota Vikings quarterback Brett Favre warms-up prior to an exhibition NFL football game against the Kansas City Chiefs, Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Tom Olmscheid)

Minnesota Vikings quarterback Brett Favre warms up for a NFL preseason football game against the Kansas City Chiefs, Friday, Aug. 21, 2009 in Minneapolis.(AP Photo/Andy King)

Minnesota Vikings quarterback Brett Favre (4) follows quarterback teammate Tarvarls Jackson (7) onto the field for pre-game warm-ups prior to the Vikings NFL preseason football game against the Kansas City Chiefs Friday, Aug. 21, 2009 in Minneapolis. (AP Photo/Tom Olmscheid)