The difference is in the numbers.

Through seven games last season, the Dallas Cowboys had allowed an average of 25.0 points per game and had surrendered 30 or more three times - once to the lowly St. Louis Rams, who crushed the Cowboys, 34-14, in what was then their most devastating debacle of the season.

Through eight games in 2009, the Cowboys' average is down to 19.4 points allowed per game, ranking 10th in the NFL. Only once, in a last-second loss to the New York Giants, have they given up 30.

The major change on defense has come at the top. Trailing the Rams 24-7 at halftime in Week 7 last year, head coach Wade Phillips relieved defensive coordinator Brian Stewart of play-calling duties and took over himself. At the end of the season, Phillips, the architect of this particular variation on the 3-4 defense theme, fired Stewart and assumed coordinator duties himself.

Sunday, he'll face Stewart, now the Eagles' secondary coach, for the first time since a difficult parting in January. Stewart had been Phillips' friend, protege and most trusted lieutenant, the only assistant Phillips brought with him from San Diego to Dallas. But Stewart was let go after he reportedly was told he'd be back.

"It's really a personal thing between he and I as far as what was said and what wasn't said and all those things," an uncomfortable Phillips said this week. "I think the world of Brian Stewart and I always will. So I'll just leave it at that."

Many of the players were just as fond of Stewart, and his dismissal stirred an odd combination of surprise, resentment and relief in the locker room.

"There were a lot of mixed emotions," defensive end Stephen Bowen said. "But, you know, if there's anyone you want to take over the defense, you'd want it to be Wade, so I think everyone was excited about that."

"Everybody knows the nature of this business," end Jason Hatcher added. "You're here one day, gone the next. But Stew's a great person and a good coach, and when you lose a guy like that, it makes a difference. He's missed around here. He wasn't a bad play-caller at all. It's just that we've gelled as a defensive unit, and now we're able to do more in the scheme because we understand it better."

The proof, though, is on the field, and in that sense, the switch has been mostly positive for the Cowboys. After Phillips took over the play-calling last season, the defense improved significantly - until a pair of late-season meltdowns against Baltimore and the Eagles - and while Dallas ranks a humble 22nd in total defense this season, opponents are having trouble putting points on the board.

Whether any of that can be attributed to the man in charge is a matter of debate, even among the Cowboys.

Phillips said the changes have been small, aimed at taking advantage of players' strengths. That includes the use of more man-to-man coverage lately to take advantage of the improvement of young cornerback Mike Jenkins and the return from injury of safety Gerald Sensabaugh.

But some players said they have seen major alterations.

"I think it's changed a lot," Bowen said. "This is his defense, so guys have more of an understanding of what he really wants to happen. Before, we had to go through coach Stew to find out what's going on, but now we're going straight to the source."

Not everyone shares that opinion. End Marcus Spears said the defense under Phillips is "the absolute same" as it was under Stewart. Linebacker Bradie James said the only difference is that Phillips "makes good adjustments."

Sunday, Phillips will have to adjust to an offense bolstered by Stewart's inside knowledge of the Cowboys' defensive scheme and personnel. The Eagles' coaches have been picking Stewart's brain this week, seeking an edge. But while the Cowboys acknowledge Stewart has information to share, they said the impact of those insights will be minimal once the game begins.

"None of that matters," Spears said. "When we play Philly, New York or Washington, they know what we're going to do. We just play football, man.

"You have no control over any of that as a player. You just go play for whoever's calling the plays. You can't take this game too personally, because things are going to change. Coaches are going to change, players . . . With a new season, new things come."