KANSAS CITY, Mo. -- The new starting quarterback of the Kansas City Chiefs is a former first-round draft pick on a one-year deal whose career thus far has been a disappointment.

His backup is a team captain whose long-term contract made him the face of the franchise.

Chiefs coach Romeo Crennel announced Monday that Brady Quinn will be under center when the Chiefs play Oakland on Sunday, and Matt Cassel will serve as the backup for the foreseeable future after struggling mightily through the first five games of the season.

"I felt like the most impactful move I could make to get everybody's attention was to change the quarterback," Crennel said. "I think that will get everybody's attention, and hopefully that impacts the team because the quarterback position is the one that has the spotlight on him."

Crennel said he informed both quarterbacks he was making a change Monday morning. The rest of the team learned of the move shortly before practice.

"Look, I'm excited about the opportunity," Quinn said. "There's always pressure, but pressure is what you make of it. As a quarterback in this league, you're used to it."

The acquisition of Cassel in a trade with New England was the first major move that Chiefs general manager Scott Pioli made after taking the job in Kansas City. His second was to sign Cassel to a $63 million, six-year deal that still has two years remaining.

Quinn is playing on a one-year deal worth $1.5 million.

"Am I going to say I'm happy about the situation? Absolutely not. I'm frustrated," Cassel said after practice. "But at the same time, I'm a team captain on this team. I care about this team and again, as we move forward, I'm a big boy. I'm not going to hang my head. I'm going to do what I've always done, which is work hard -- work tremendously hard."

Quinn started for the first time since 2009 in a loss at Tampa Bay two weeks ago, when Cassel was still feeling the effects of a concussion sustained the previous week against Baltimore.

Crennel said at the time he wasn't planning to make a permanent move, but he reconsidered after spending the bye week evaluating both quarterbacks, and coming to the realization that Kansas City desperately needed a spark following a 1-5 start.

"I'm not saying Matt Cassel is the reason we are where we are," Crennel said. "We need to coach better and we need to play better, and if we do those things, we can be better, but my biggest deal was my gut was telling me we need to impact that team by changing that dynamic."

Cassel, who missed the end of last season with a hand injury, hasn't been nearly as good as he was two years ago, when he led the Chiefs to the AFC West title and was voted to the Pro Bowl.