Kiffin said he could tell Josh McCown and Daunte Culpepper who won the job as early as Sunday, but wants to keep the decision under wraps to make the Lions prepare for two different quarterbacks.
Culpepper was sharper in the final exhibition game Thursday at Seattle, completing 11-of-19 passes for 108 yards and leading the offense to its only touchdown in a 19-14 loss. But Culpepper also threw an interception.
McCown started the game and went 5-for-12 for 75 yards in four series.
"They both did well but could have played better," Kiffin said. "It was not their best game."
Culpepper is not as familiar with the offense as McCown after signing with the team July 31 when it became apparent that top draft pick JaMarcus Russell would not be in camp anytime soon because of a contract dispute.
Russell remains unsigned and the Raiders could enter the season without their quarterback of the future on the roster. That leaves the job to either McCown or Culpepper.
"Whatever my role is, I accept it," Culpepper said after the game. "That's how I'm going forward with it. If they feel I'm ready to play, then I'll be ready mentally. If not, I'll be ready to help out in every situation. So in my mind, it really doesn't matter. Obviously I want to be out there. But I don't want to miss the whole fact that I have to get ready to go out there."
Culpepper has shown that his surgically repaired right knee is healthy this preseason. He's thrown four touchdown passes with only one interception as he tries to put last year's disappointment in Miami behind him.
HARRISON SUSPENDED -- New England safety Rodney Harrison will be suspended four games for violating the league's substance abuse policy.
"Tomorrow, the commissioner will announce that I've been suspended," a somber Harrison said in a hastily announced conference call.
Although the hard-hitting defensive back said he has never used steroids, "I did admit to the commissioner that I did, in fact, use a banned substance."
"My purpose was never to gain a competitive edge," he said. "Rather, my use was to accelerate the process of recovering from injuries."
The suspension was first reported by ESPN.com, which said Harrison admitted to federal investigators that he obtained human growth hormone. Harrison did not take questions about the details of the suspension.
QUICK HITTERS -- Jacksonville is parting ways with quarterback Byron Leftwich after four frustrating, injury-filled seasons. Coach Jack Del Rio said the team plans to trade or release the former first-round draft pick. Del Rio named mobile backup David Garrard his starter. ... Seven-time Pro Bowl defensive end Michael Strahan has decided to end his holdout and return for a 15th season with the New York Giants.
Preseason Games
BENGALS 14, COLTS 6, at Cincinnati -- Kicker Aaron Elling hurt his right knee trying to make a tackle on the second-half kickoff, leaving the Bengals without a kicker. Elling was brought in Wednesday, two days after Shayne Graham bruised his right hip while trying to make a tackle against Atlanta.
FALCONS 13, RAVENS 10, at Atlanta -- Not even Ravens $40 million running back Willis McGahee could stir much excitement. McGahee was one of the few players with name recognition to play in a game decided by second-string kickers.
Matt Prater, in just his second day with Atlanta, kicked two fourth-quarter field goals.
