Matt Cassel had never been in the right place at the right time, and that appeared destined to go down as an epitaph for his career.

Then Tom Brady, who hadn't missed a game since becoming a starter in 2001, suffered a season-ending knee injury. That the New England Patriots did not go down with Brady is in large part due to the player who had not started a game at quarterback since high school prior to September.

If Cassel, who will lead the 7-4 Patriots against the 8-3 Steelers Sunday, has not replaced Brady, he has at least done a pretty fair imitation of the NFL's reigning MVP.

Cassel has thrown for over 400 yards the past two weeks and is only the fifth player in NFL history to accomplish that feat. He has a better passer rating than Indianapolis Colts quarterback Peyton Manning and the Steelers' Ben Roethlisberger.

Cassel also has completed a higher percentage of his passes than the New York Giants' Eli Manning and San Diego Chargers' Philip Rivers, who leads the NFL in passer rating.

"He's doing an amazing job, and I think the one thing he has is confidence coming into this game," Steelers free safety Ryan Clark said. "You do it against the Steelers, you did something. I think it will be a big challenge for us -- but also for him."

Tale of the tape

Here

is how Patriots quarterback Matt Cassel and Steelers QB Ben

Roethlisberger compare this season.

Comp.

Att.

Pct.

Yds

TD

INT

Rating

Rush

Yards/TD

Ben Roethlisberger

191

310

61.6

2,223

11

11

80.5

19-43/2

Matt Cassell

238

359

66.3

2,615

13

8

90.5

53-199/2

Cassel can indeed take a big step toward legitimizing what he has done in little more than half a season if he plays well against a unit that leads the NFL in run defense, pass defense and total defense. Nothing, however, suggests that the success Cassel has enjoyed to this point is a fluke.

The 6-4, 230-pounder is a classic drop-back passer, but he can also hurt opposing defenses with his legs. The New York Jets found that out a couple of weeks ago when Cassel torched them for 400 passing yards and added 62 rushing.

"You don't ever want to see anything happen to Tom, but I think that everybody was excited to see what Matt would do with his opportunity," Patriots coach Bill Belichick said, "because he does have some good tools to work with, and he has had four years in our system."

Cassel didn't throw many more passes at USC as he did in New England before Brady got hurt, as he played behind a pair of Heisman Trophy winners in Carson Palmer and Matt Leinart.

Cassel and Leinart waged a spirited battle for the starting job after Palmer, the first overall pick of the 2003 NFL Draft, left. The two were so close that USC coach Pete Carroll didn't settle on a starter until fall practice of 2003. Even after he didn't win the starting job, Cassel said he thought he would get an opportunity if Leinart faltered.

That never happened, and it took the injury to Brady for Cassel, a seventh-round pick by the Patriots in 2005, to get his chance.

"I have been preparing for the day for a long time, and it finally showed up," Cassel said.

So has Cassel, and in watching recent tape of him in preparation for Sunday, the Steelers saw a different quarterback than the one who got thrust into duty in early September.

"He looks a lot more comfortable," Steelers inside linebacker James Farrior said. "It seems like he's getting better and better and improving every week."

With each passing week, Cassel is positioning himself for a big payday.

He will be an unrestricted free agent after the season and figures to have no shortage of suitors given how demand far exceeds supply when it comes to quality quarterbacks in the NFL.

There are even questions as to whether the Patriots will try to retain Cassel. That is how well he has played in Brady's absence.

"I had to get my bearings under me and understand my role as a leader -- and your role definitely changes when you go from a backup to a starter," Cassel said. "Learn what your role is and get the other players to believe in you and gain confidence in you."