But with top draft pick JaMarcus Russell still battling over the terms of his first NFL contract and out of training camp, the itinerant five-year veteran McCown has an opportunity to make the most of his spot atop the Oakland Raiders' depth chart, starting with a preseason game Saturday against the Arizona Cardinals.
"It's something I plant to build on," said McCown, who starts Saturday against the franchise with which brought him into the league. "I'm excited about the opportunity and to help the team bring some consistency to the quarterback position."
First-year Raiders coach Lane Kiffin stressed that all three of his veteran quarterbacks -- McCown, Andrew Walter and Daunte Culpepper -- will get equal snaps in the game. But it will be McCown, at least for this game, who will work with the first-unit offense (at least initially), and try to convince Kiffin and his staff that he should be the starter until Russell eventually signs and is groomed to compete for the No. 1 spot.
McCown, 28, is aware that first impressions are critical in the NFL, and especially with the kind of battle being waged for the Raiders' starting job. He noted earlier this week that his goal on Saturday is to maintain an even keel, not attempt to force the issue in an attempt to make big plays, and let the game come to him.
Oakland acquired McCown from the Detroit Lions during the draft in April in a trade that also brought the Raiders former first-round wide receiver Mike Williams. There was plenty of speculation then that McCown, whose résumé includes 22 career starts since being drafted by the Cardinals in 2002, would become the caretaker quarterback, starting for a year or so while Russell served his apprenticeship. Such talk was enhanced when Walter, who started eight games in 2006, missed much of the spring workouts following arthroscopic knee surgery.
But Walter has returned, the Raiders added Culpepper as a free agent, and the battle for the starting job is now a three-pronged one. Kiffin has not offered any hints about how he might be leaning, but did laud McCown's work and leadership in a recent scrimmage.
In 35 career appearances, McCown has completed 498 of 862 passes for 5,431 yards, with 25 touchdown passes and 29 interceptions, for a 72.1 passer efficiency rating.
The starting nod on Saturday is the latest carrot dangled in front of McCown, who started 13 games for the Cardinals in 2004. He signed with the Lions last spring as an unrestricted free agent, with the understanding he would compete with veteran Jon Kitna for the starting job. Kitna, however, was named the starter even before training camp began, and he took every snap for the Lions in 2006, the first player in franchise history to do so.
Now with the Raiders, his third team in three years, McCown has viewed it as another fresh start and another opportunity to win a starting commitment. Even with the shadow of the unsigned Russell hovering over all the quarterbacks in camp, McCown, who is in the final year of his contract, is eager to make this chance count.
"Not anxious, just eager, you know?" McCown said. "I just want to play, to play well, and then we'll see how things shake out."
Len Pasquarelli is a senior NFL writer for ESPN.com.