The New England Patriots sent Matt Cassel to the Kansas City Chiefs and a message to their own fans: don't worry about Tom Brady's knee.

One question, though, remained.

How could the Patriots obtain only a second-round draft choice for a solid, young quarterback and a 12-year veteran leader, linebacker Mike Vrabel?

That mystery persisted yesterday after the Patriots announced the trade for the 34th pick in this year's draft, which the Chiefs earned with a franchise-worst 2-14 record.

Cassel, who hadn't started the previous seven seasons with Southern California and the Patriots, led New England to an 11-5 record, but no playoff berth, after Brady suffered a season-ending knee injury in the opener against Kansas City.

Cassel's steady improvement sent his stock soaring as he entered free agency. So the Patriots put the franchise tag on him, requiring any team that signed him to give them two first-round picks. But that tag would have cost the Patriots $14.65 million if they kept Cassel as insurance if Brady's health was questionable.

By shipping him out so early, they must be sure that 2007 NFL MVP Brady will be ready for the regular season after undergoing surgery for torn ligaments in his left knee on Oct. 6 and a later operation for an infection in the knee.

On Feb. 18, Brady said his recovery was on schedule for him to be ready for the opener.

"I'm feeling great. I'm feeling really good. Everything is progressing just as I expected," he said at a charity event.

BRONCOS

SIGN SAFETY DAWKINS

The Denver Broncos have signed seven-time Pro Bowl safety Brian Dawkins, who spent his entire 13-year career with the Philadelphia Eagles. Terms of the deal were not released.

Although Dawkins turns 36 next season and is clearly on the downside of his career, he brings a hard-hitting style and leadership qualities coveted by new Broncos coach Josh McDaniels.

The Broncos also signed free agent safety Renaldo Hill, who helped lead the Miami Dolphins' turnaround last season.

COWBOYS

BACKUP QB KITNA SIGNS

The Dallas Cowboys took care of one of their top offseason priorities yesterday when they acquired quarterback Jon Kitna as the likely backup for Tony Romo.

Then they went out and signed linebacker Keith Brooking to a three-year deal worth about $6 million — with about $2.5 million guaranteed.

The Cowboys got Kitna from Detroit for starting cornerback Anthony Henry.

EAGLES

BROTHER, CAN THEY BLOCK

Stacy Andrews and his little brother will form a big wall in front of Donovan McNabb.

The Philadelphia Eagles bolstered their offensive line by signing Andrews to a six-year contract yesterday. Andrews spent his first five seasons with Cincinnati and is the older brother of Eagles right guard Shawn Andrews, a former All-Pro coming off a difficult year.

The massive Stacy Andrews — he's listed at 6-foot-7, 342 pounds — is a versatile lineman who can play tackle or guard.

49ERS

EX-TITAN JONES SIGNS

Receiver Brandon Jones has agreed to join the San Francisco 49ers, getting a five-year contract worth $16.5 million.

Jones spent his first four NFL seasons with Tennessee, where he caught 41 passes for 449 yards and a touchdown last season. He was hampered by significant injuries in two of his four seasons, including a groin injury that limited him to nine games in 2007.

RAMS

CENTER BROWN CASHES IN

The St. Louis Rams made Jason Brown the highest-paid center in the NFL yesterday, signing the former Ravens lineman to a five-year, $37.5 million deal — including $20 million guaranteed.

"There is the potential to do something special," Brown said after giving coach Steve Spagnuolo a hug and holding up a No. 60 jersey at an introductory news conference. "I'm telling you right now we're going to be better than a .500 team."

ELSEWHERE

Bills: Offensive lineman Geoff Hangartner, a 6-foot-5, 315-pounder, who's played both center and guard during his previous four years with the Carolina Panthers, signed a four-year deal with Buffalo. Financial terms were not announced.

Giants: New York bolstered its defense yesterday, signing former Atlanta Falcons linebacker Michael Boley to a five-year, $25 million contract. The 26-year-old Boley is expected to be given a shot at winning the weakside job. He played the strongside for Atlanta.

Jets: New York shored up its shaky secondary, acquiring two-time Pro Bowl cornerback Lito Sheppard from Philadelphia for undisclosed draft picks. The Jets also re-signed right guard Brandon Moore, who was cut Thursday, to a four-year, $16 million deal.

Texans: Arizona Cardinals free agent defensive end Antonio Smith signed yesterday with Houston. Terms of the deal were not disclosed. The Texans also re-signed free agents: tight end Joel Dreessen, defensive end Stanley McClover, center Chris White and safety Eugene Wilson.