Dallas' Rob Ryan: Tom Brady best

IRVING, Texas -- Dallas Cowboys defensive coordinator Rob Ryan vowed that he's done comparing players after saying two weeks ago that his defense practiced against two receivers who are better than Detroit's Calvin Johnson.

When discussing the quarterback he's preparing for, he said there is no comparison.

"You're talking about the best quarterback, in my opinion, that's ever played the game," Ryan said. "Hell, I know that. He's that good.

"You obviously have to attack the source of the passing game and he happens to be the best in the league here. Every ball is going to be on the money, every throw is going to be out of his hand quick and it's going to be to the right place. You have to be at your best."

Brady's statistics and accomplishments speak for themselves. He owns three Super Bowl rings, two NFL MVP awards, the single-season record for touchdown passes and is on pace this year to break the record for passing yards in a season.

Ryan, who was the Patriots' linebackers coach from 2000 to 2003, has similar respect for New England coach Bill Belichick.

"You can have Bill Parcells as a head coach and Vince Lombardi as a D-coordinator and Bill Walsh as the offensive coordinator and I think Belichick would beat them by two touchdowns if it came down to coaching," Ryan said. "It's going to come down to players and coaches and everything."

Ryan relishes the challenge of playing the Patriots, who on Sunday can match the NFL record for most consecutive regular-season games of at least 30 points scored.

They have scored at least 30 in 13 consecutive games, one fewer than Kurt Warner's St. Louis Rams did in 1999 and 2000.

The Patriots' streak started after the last time they faced a Rob Ryan defense. The Cleveland Browns got the best of Brady and Co. in a stunning 34-14 win last season.

Ryan's Dallas defense, which enters the game ranked second in the league, features more talent. He's eager to see how the Cowboys perform against the Patriots, who have the league's top-ranked offense.

"This is a fun week," said Ryan, who referred to the Patriots as the ultimate challenge. "Why is it fun? You're going against the best offense in football that runs the score up on people every week. Because I want our guys and me and our coaching staff -- headed by [defensive quality control coach] Ben Bloom, headed by [quality control coach] Dave Borgonzi -- to go down there and kick their ass."

While Ryan had nothing but praise for the Patriots, he indicated that he had no regret about his remarks regarding Johnson, who scored the last two touchdowns during Detroit's come-from-behind win over Dallas. That prompted Detroit coach Jim Schwartz to open his postgame news conference with a sarcastic comment about being glad that the Cowboys' third-best receiver played for the Lions.

"I'm not going to compare anybody any more, even though Dez Bryant did catch two TD passes," Ryan said Friday. "So did the other guy. I've given that up. Hell, I've taken a beating for that."

Tim MacMahon covers the Cowboys for ESPNDallas.com.